Year 12 Chemistry acidic environment Le Chatelier s principle
|
|
- Barbra Charles
- 5 years ago
- Views:
Transcription
1 CD321 cd321 Year 12 Chemistry acidic environment first name last name cd321
2 2
3 3 syllabus Students learn to: Students: 2. While we usually think of the air around us as neutral, the atmosphere naturally contains acidic oxides of carbon, nitrogen and sulfur. The concentrations of these acidic oxides have been increasing since the Industrial Revolution identify oxides of non-metals which act as acids and describe the conditions under which they act as acids analyse the position of these nonmetals in the Periodic Table and outline the relationship between position of elements in the Periodic Table and acidity/basicity of oxides define Le Chatelier s principle identify factors which can affect the equilibrium in a reversible reaction describe the solubility of carbon dioxide in water under various conditions as an equilibrium process and explain in terms of Le Chatelier s principle identify data, plan and perform a first-hand investigation to decarbonate soft drink and gather data to measure the mass changes involved and calculate the volume of gas released at 25 C and 100kPa analyse information from secondary sources to summarise the industrial origins of sulfur dioxide and oxides of nitrogen and evaluate reasons for concern about their release into the environment identify natural and industrial sources of sulfur dioxide and oxides of nitrogen describe, using equations, examples of chemical reactions which release sulfur dioxide and chemical reactions which release oxides of nitrogen assess the evidence which indicates increases in atmospheric concentration of oxides of sulfur and nitrogen calculate volumes of gases given masses of some substances in reactions, and calculate masses of substances given gaseous volumes, in reactions involving gases at 0 C and 100kPa or 25 C and 100kPa explain the formation and effects of acid rain
4 Classification of oxides Metallic oxides Most oxides of metals are bases and, if soluble in water, e.g. Group I oxides and CaO and BaO, they form alkaline solutions. Some insoluble oxides are MgO, CuO, Fe2O3and Ag 2O. They can be neutralised by strong acids to form salts and water. Common basic oxides include: Na O, MgO, CaO, FeOand CuO. For example: 2 CaO s 2HCl CaCl H O 2 2 Soluble basic oxides react with water to form alkaline solutions. Alkaline solutions contain hydroxide ions. Red litmus turns purple in these solutions. All Group I oxides are soluble in water. For example: 2 2 K O s H O 2K 2OH Non-metallic oxides Non-metallic oxides are often acidic (although some are neutral). They can be neutralised by strong bases to form salts and water. Common acidic oxides include: CO 2, NO 2, SO 2, SO 3 and P4O 10. For example: CO g 2KOH K CO H O Phosphorus pentoxide reacts with water to form phosphoric acid. P O s 6H O l 4H PO aq Table (1) summarises properties of metal oxides and non-metal oxides. Property Metal oxide Non-metal oxide Bonding Strong ionic bonds extend throughout the lattice Strong covalent intramolecular bonds (within the molecule). Weak intermolecular forces (between molecules) State at room temperature Solid Gas MP, BP High Low Table (1) Properties of metal oxides and non-metal oxides
5 5 Neutral oxides The neutral non-metallic oxides include: CO, NO and N2O. Amphoteric oxides Some oxides are amphoteric. Amphoteric oxides can be neutralised by either an acid or a base. Common amphoteric oxides include: Al2O 3, ZnO, PbO, SnO and As2O 3. For example: ZnO as a base: ZnO s H SO ZnSO H O A solution of zinc sulfate forms Al O 3H 6H O 2 Al H aq Al O 3H 2O 2Al OH aq Question 1 Which of the following is not correct about metallic oxides? (A) (B) (C) (D) Metallic oxides are basic. Metallic oxides are ionic compounds Metallic oxides react with acids to produce salt and water Metallic oxides do not dissolve in water at all Question 2 Which of the following is correct about acidic oxides? (A) (B) (C) (D) Non-metallic oxides are acidic oxides Acidic oxides react with acids to produce water and salt All non-metallic oxides are acidic Acidic oxides are ionic substances Question 3 Which of the following correctly explains amphoteric oxides? (A) (B) (C) (D) Amphoteric oxides can react with water Amphoteric oxides can be neutralised by either an acid or a base Amphoteric oxides can act as a Bronsted acid or base Amphoteric oxides are non-metallic oxides
6 6 Question 4 Classify the following oxides as acidic, basic, amphoteric or neutral: (a) Zinc oxide Nitrogen monoxide (c) Sulfur trioxide (d) Nickel oxide Question 5 Identify oxides which act as acids and describe the conditions under which they act as acids
7 Periodic trends of oxides The locations of basic, amphoteric and acidic oxides in the periodic table are shown in figure (1). Figure (1) Periodic table and oxide classification General trends of oxides in the Periodic table As metallic character increases, the basic property of an oxide increases. Oxides of elements in left hand side of the Periodic table are basic. Moving to the left of the Periodic table, the basic property of an oxide increases. Oxides of elements in right hand side of the Periodic table are acidic. Some of metallic oxides are amphoteric Some non-metallic oxides are not soluble in water and neutral Group VIII elements do not form oxides.
8 8 The following tables show properties of oxides of main groups in the Periodic Table. Group IV Table (2) Properties of group IV oxides GROUP IV Carbon dioxide CO 2 Silicon dioxide SiO 2 Structure covalent molecular covalent network Physical properties gas at room temperature solid at room temperature Effect on living things essential as a source of carbon for photosynthesis Effect on the rate of emission of CO 2, and atmosphere other greenhouse gases is increasing; in the case of CO 2, this is mainly due to fossil-fuel burning Chemical properties Group V GROUP V and deforestation soluble in water forming an acidic solution containing 5 H2CO3 K a , this accounts for the acidity of carbonated water; reacts with hydroxide ions to form carbonates and hydrogen carbonates in solution almost insoluble 10 about 10 K a forms a wide range of silicates with the hydroxide ion Table (3) Properties of group V oxides Acidic oxides of nitrogen Acidic oxides of phosphorus nitrogen dioxide NO 2, dinitrogen phosphorus (III) oxide P2O 3, trioxide N2O 3, dinitrogen pentoxide phosphorus (IV) oxide PO 4 10 NO 2 5 Structure covalent molecular covalent molecular Effect on NO2 is a serious atmospheric pollutant atmosphere in photochemical smog formation in cities Chemical both the stated oxides of nitrogen are both oxides of phosphorus are water properties water soluble NO 2 3 is the anhydride of soluble; PO 2 3is the anhydride of Acid properties of the oxides nitrous acid HNO 2 (weak acid). 2 5 the anhydride of nitric acid HNO 3 (strong acid) NO 2 5is strongly acidic; NO 2 3 is weakly acidic NO is Note: The acidic nature of the oxides of Group V decreases down the group. orthophosphorous acid H3PO 3; PO 4 10 is the anhydride of orthophosphoric acid H 3 PO 4 PO 2 3 is weakly acidic (weaker than NO 2 3); PO 4 10 is strongly acidic
9 9 Group VI Table (4) Properties of group VI oxides GROUP VI Sulfur dioxide SO 2 Sulfur trioxide SO 3 Structure covalent molecular covalent molecular Physical SO 2 is a gas at room temperature SO 3 is a solid at room temperature properties (melting point 62 C) Effect on atmosphere increases in the amount of sulfur dioxide in the atmosphere have led to 'acid rain', particularly in cities in the Chemical properties Northern Hemisphere SO has a low solubility in water and 2 forms sulfurous acid H2SO 3; it reacts with hydroxide ions to form sulfites and hydrogen sulfites in solution SO 3 dissolves in water to form H SO, which is a strong acid; it 2 4 reacts with hydroxide ions to form sulfates and hydrogen sulfates in solution Group VII With the exception of F2 O, all the oxides are acidic. The oxides of chlorine are strong oxidants. ClO2 is used for bleaching in the paper industry and as a germicide. It is also used as an improving agent for flour. 2ClO 2 H2O HClO 2 HClO 3 Another oxide of chlorine, Cl2O 7, dissolves in water to form a powerful oxidising acid called perchloric acid HClO. 4
10 10 Question 6 Which of the following shows only neutral oxides? (A) CO, NO, NO 2 (B) CO, NO, N 2 O (C) CO 2, NO, N 2 O (D) CO, N 2 O 4, NO 2 Question 7 Complete the following general rules: (a) Oxides of non-metals are oxides. Oxides of metals are oxides. Question 8 Complete the key in the following Periodic Table to show which elements form acidic oxides, basic oxides, amphoteric oxides and which do not form any oxides. (a) (c) (d)
11 11 Question 9 Metals form basic oxides. Basic oxides will dissolve in water to form an hydroxide. Complete the following equation to illustrate this. Magnesium oxide water MgO(s) H O l Question 10 Basic oxides react with acids to form water and a salt. Use an equation to show the reaction of basic magnesium oxide with hydrochloric acid.
12 Equilibrium and Le Chatelier s principle Not all chemical reactions proceed to completion. Many reactions are reversible. As a reaction proceeds, the rate of the forward reaction decreases as the reactants are consumed. The increasing concentration of products leads to an increase in the reverse reaction rate in which reactants are reformed. Eventually, a dynamic equilibrium state is reached when the rate of the forward reaction exactly equals the rate of the reverse reaction. In a reversible reaction there will always be some reactants and products present. The characteristics of a system at equilibrium are: Closed system - no matter or energy can enter or leave. Macroscopic properties are constant - colour, pressure, state and temperature do not change. Concentrations of reactants and products are constant. Microscopic changes continually take place between reactants and products. Rate of forward reaction Rate of reverse reaction.
13 13 When a catalyst is added to a reversible system it lowers the activation energy for both the forward and reverse reactions. The rates of both the forward and reverse reactions are increased equally so that the catalyst does not affect the relative proportions of reactants and products. Le Chatelier s principle If a change is made to an equilibrium system, then the system alters in a way that counteracts the change. Various factors can affect the equilibrium in a reversible reaction. These include the following. Concentration If the concentration of a reactant is increased for a system in equilibrium, then the forward reaction rate increases and the position of the equilibrium is shifted to the product side. If the concentration of a product is increased, the equilibrium shifts back to the side of the reactants.
14 14 Concentration examples A solution of potassium dichromate is prepared. It is orange-yellow in colour. Cr O H O l 2CrO 2H orange yellow Diluting the system with water: The solution becomes more yellow as the additional water causes the equilibrium to shift to the product side. Adding hydrochloric acid: The solution becomes more orange as the additional hydrogen ions causes the equilibrium to shift to the reactant side. A cobalt chloride solution is pink. The addition of concentrated hydrochloric acid (a source of Cl ) causes the system to change from pink to a blue-purple colour. Le Chatelier s principle explains this observation. The addition of more product(cl ) changes the equilibrium. To counteract the change, the concentration of chloride ions must be reduced. This is achieved by some chloride ions reacting with the pink cobalt ions to form the blue cobalt ions. Thus, the equilibrium shifts to the left to counteract the change. 2+ CoCl 6H O Co H O 4Cl Blue pink Total gas pressure In a system involving gases, the application of pressure (by reduction in volume of the vessel) will lead to a shift in the equilibrium that favours the side of the equilibrium with lower amounts of reacting substances. If volume increases, it causes a decrease in pressure. Or if volume decreases, it causes an increase in pressure. Each case will produce the same result of the corresponding pressure effect. Total gas pressure example A mixture of NO2 gas and NO 2 4 gas is in equilibrium. The mixture is pale brown at room temperature. 2NO g N O g Brown colourless If the reaction mixture is placed in a syringe and the volume slowly reduced so as not to heat up the gas, the mixture becomes a much lighter brown as the equilibrium shifts to the right (the product side has fewer molecules than the reactant side).
15 15 Temperature Some reactions are endothermic and others are exothermic. In an endothermic equilibrium, an increase in temperature causes the equilibrium to shift to the product side. In an exothermic equilibrium, an increase in temperature causes the equilibrium to shift to the reactant side. Type of reaction Effect on equilibrium when: Temperature increases Temperature decreases Exothermic reaction Shift left favours reactants Shift right favours products Endothermic reaction Shift right favours products Shift left favours reactants Temperature example Table (5) Effect of temperature on equilibrium The decomposition of magnesium carbonate is an endothermic process. MgCO s heat MgO s CO g 3 2 If the system is heated, then the equilibrium shifts to the right to produce more carbon dioxide gas. Thus, thermal decomposition of magnesium carbonate is favoured by high temperatures. Question 11 Which of the following is a correct statement of Le Chatelier s principle? (A) (B) (C) (D) An equilibrium system will always move to the left when it is heated. Increasing the pressure on a reaction vessel will increase the rate of reaction. The rate of reaction in an equilibrium system depends on the presence or absence of a catalyst. If a system is in equilibrium and it is changed in some way, then the system adjusts to minimise the change. Question 12 How is an equilibrium system represented in a chemical equation?......
16 16 Question 13 Which of the following is incorrect about dynamic equilibrium? (A) (B) (C) (D) Rate of forward reaction is equal to the rate of backward reaction The concentration of reactants is the same as the concentration of products Macroscopic properties are constant Microscopic properties continuously take place Question 14 (a) Which of the following reactions would not be affected by a change in the volume of the container? (A) 2NO2 g N2O4 g (B) H2g I2g 2HI g (C) 2CO2 g H2Ol H2CO3 aq (D) 2SO g O g 2SO g Explain your choice
17 17 Question 15 If the reaction 4NH g 5O 4NOg 6H Og the following changes on: is at equilibrium, what would be the effect of i. the concentrations of all the species, and ii. the rates of the forward and reverse reactions? (a) Adding more O 2 to the system. Reducing the concentration of NO. Question 16 (a) The equation 2SO g H Ol H SO aq represents an equilibrium system established in a closed container. What happens if the size of the container is increased? (A) (B) (C) (D) The equilibrium moves to the left. Less sulfur dioxide is produced. The equilibrium position is unchanged. Sulfurous acid is produced more rapidly. Explain the response of the system to the change.
18 18 Practice Questions Question 17 Which of the following shows only amphteric oxides? (A) Al 2 O 3, ZnO, SO 2 (B) O, N 2 O, CO (C) Al 2 O 3, ZnO, PbO (D) ZnO, MgO, PbO Question 18 Which of the following is incorrect about the general trends of oxides in the Periodic Table? (A) (B) (C) (D) Most oxides of elements in the right hand of the Periodic table are acidic Most oxides of elements in the left hand of the Periodic table are basic As metallic character increases the basic property of an oxide decreases Group VIII elements do not form oxides Question 19 Which of the following sets contains only compounds which are acidic in aqueous solution? (A) (B) (C) (D) Carbon dioxide, sulfur dioxide, dinitrogen monoxide Phosphorus pentoxide, nitrogen dioxide, sulfur dioxide Magnesium oxide, nitrogen monoxide, carbon dioxide Barium oxide, potassium oxide, magnesium oxide Question 20 Which of the following equations correctly shows an oxide dissolving in water to form an acid? (A) 2NO g O2g 2NO2g (B) CO2 g H2Ol H2CO3 aq (C) MgO s H2Ol Mg OH aq 2 (D) SO g H Ol H SO aq
19 19 Question 21 (a) Which two oxides of non-metals are only slightly soluble in water and form neutral solutions? (A) (B) (C) (D) Carbon monoxide and dinitrogen monoxide Carbon dioxide and sulfur dioxide Nitrogen monoxide and carbon dioxide Nitrogen dioxide and nitrogen trioxide State the formula for these two neutral oxides. Question 22 Rank the following oxides from most basic to most acidic. Cl2O 7, Sb2O 3, NO 2, BaO.
20 20 Question 23 Choose 3 oxides of elements in the third period of the Periodic Table. One must be an acidic oxide, one basic and one amphoteric. Use these examples to describe the meaning of these terms and give equations for reactions you describe.
21 21 Question 24 The following is a simplified Periodic table. (a) Which elements in the Periodic table form oxides that react with acids? Which elements in the Periodic table form oxides that react with bases? (c) Which elements in the Periodic table form oxides that react with both acids and bases? (d) Which elements in the Periodic table do not form oxides? (e) Which elements in the Periodic table form oxides that are neutral? Question 25 When does a chemical reaction reach a state of dynamic equilibrium?
22 22 Question 26 Outline any effect of a catalyst on an equilibrium reaction. Question 27 Consider the following equilibrium between the colourless gas dinitrogen tetroxide and the brown N O g 2NO g gas nitrogen dioxide: (a) When a sealed tube containing these gases in equilibrium is heated, the brown colour of the mixture darkens. Which statement explains this change? (A) (B) (C) (D) Equilibrium shifts to the right because the forward reaction is endothermic. Heating causes gases to expand so pressure increases and the reaction shifts right. Equilibrium shifts right because the forward reaction is exothermic. The deepening brown colour is due to the expansion of gases. Explain the effect of temperature changes on equilibrium reactions.
23 23 Question 28 When Ca OCl 2 is used to disinfect swimming pools, the following equilibrium is set up: Ca OCl aq 2H Ol 2HOCl aq Ca OH aq (a) What happens to the ph of the pool water when acid is added? (A) (B) (C) (D) The ph rises as acid is added and then falls. The ph falls and then rises towards its original value. The ph stays constant. The ph rises and stays higher than its original value. Explain your answer.
24 24 Question 29 (a) To which of the following equations would Le Chatelier s principle be applicable? (A) BaO s H2Ol Ba OH aq 2 (B) HCl aq NaOH aq H2Ol NaCl aq (C) CO2 g H2Ol H2CO3 aq (D) Mg s HCl aq MgCl aq H g 2 2 Under what conditions could Le Chatelier's principle be applied to this reaction? Question 30 Complete the following to summarise the characteristics of a reversible system that has reached equilibrium. (a) It is a system - no matter or energy enters or leaves the system. Macroscopic properties (e.g. state, colour, temperature and pressure) stay (c) Concentrations of reactants and products stay (d) Continual change occurs between reactants and products. (e) The rate of forward reaction rate of reaction.
25 25 Question 31 Brown NO 2 gas and colourless NO 2 4 gas are in equilibrium in a closed container at room temperature. The reaction is exothermic NO g N O g Use Le Chatelier s principle to predict the effect of the following changes to this equilibrium: (a) Cooling the vessel with ice. Compressing the gas mixture at constant temperature.
26 26 Question 32 The reaction for the production of carbon monoxide and hydrogen gases is: C s H O g CO g +H g. 2 2 If the system is at equilibrium what would be the effect of the following changes on: i. the concentrations of all the species, and ii. the rates of the forward and reverse reactions? (a) Increasing the volume of the system. Increasing the pressure on the system.
27 27 Question 33 If thesystem 2CO g O g 2CO g 564 kj is at equilibrium, what would be the effect of the following changes on: 2 2 i. the concentrations of all the species, and ii. the rates of the forward and reverse reactions? (a) Increasing the temperature. Reducing the temperature:
28 28 Question 34 Consider the reaction: 2SO g O g 2SO g 99kJ What would be the effect of adding a catalyst (a) Before the system reached equilibrium? After the system reached equilibrium?
29 29 Question 35 The following diagram shows changes in the concentration of a reaction below. N ( g) 3 H ( g) 2 NH ( g) 92 kj mol (a) What happens at the time period between T 1 and T 2 What happens at time T 2? (c) Describe the effect of the changes identified in part on equilibrium and draw changes in the concentrations of reactants and products on the graph above (d) What would be the effect if the temperature is increased on the equilibrium?
30 30 Question 36 The following diagram shows changes in the concentration of a reaction below. PCl ( g) Cl ( g) PCl ( g) 124 kj mol (a) If the volume of the reaction vessel is reduced at time T 1, what would happen to the concentrations of substances and equilibrium? Draw the changes identified in part (a) on the graph above. (c) If the concentration of PCl 5 is reduced at time T 2, what would happen to the equilibrium? (d) Draw the changes identified in part (c) on the graph above.
31 31
32 32
91166 Demonstrate understanding of chemical reactivity Collated questions on equilibria
(2017:2) 91166 Demonstrate understanding of chemical reactivity Collated questions on equilibria The addition of a small amount of iron to a mixture of nitrogen and hydrogen gases helps to speed up the
More informationQUESTIONS: Equilibria AS & AS
QUESTION (2012:2) Phosphorus pentachloride gas, PCl 5 (g), decomposes to form phosphorus trichloride gas, PCl 3 (g), and chlorine gas, Cl 2 (g). The equilibrium can be represented as: PCl 5 (g) Ý PCl 3
More informationQ1. (a) State what is meant by the term activation energy of a reaction. (1)
Q1. (a) State what is meant by the term activation energy of a reaction. (c) State in general terms how a catalyst increases the rate of a chemical reaction. The curve below shows the Maxwell Boltzmann
More informationCHEMISTRY PAPER 1999
CHEMISTRY PAPER 1999 (One and a half hours) Answers to this paper must be written on the paper provided separately. You will NOT be allowed to write during the first 15 minutes. This time is to be spent
More informationCHEMICAL EQUILIBRIA. Section A Q1 The dissociation of dinitrogen tetraoxide into nitrogen dioxide is represented by the equation below.
Section A Q1 The dissociation of dinitrogen tetraoxide into nitrogen dioxide is represented by the equation below. If the temperature of an equilibrium mixture of the gases is increased at constant pressure,
More information2 EQUILIBRIUM 2.1 WHAT IS EQUILIBRIUM? 2.2 WHEN IS A SYSTEM AT EQUILIBRIUM? 2.3 THE EQUILIBRIUM CONSTANT
2 EQUILIBRIUM 2.1 WHAT IS EQUILIBRIUM? In general terms equilibrium implies a situation that is unchanging or steady. This is generally achieved through a balance of opposing forces. In chemistry equilibrium
More informationAP Chemistry Note Outline Chapter 4: Reactions and Reaction Stoichiometry:
AP Chemistry Note Outline Chapter 4: Reactions and Reaction Stoichiometry: Water as a solvent Strong and Weak Electrolytes Solution Concentrations How to Make up a solution Types of Reactions Introduction
More information(b) Increase in pressure. (1)
1 This question is about the equilibrium reaction between hydrogen and carbon dioxide. H 2 (g) + O 2 (g) H 2 O(g) + O(g) H = +40 kj mol 1 What effect would the following changes have on the rate of reaction
More informationSummary Term 2 Chemistry STPM Prepared by Crystal Goh AI Tuition Centre
Summary Term Chemistry STPM Prepared by Crystal Goh AI Tuition Centre 017713136 Period 3 elements property Na Mg Al Si P (P 4 ) Type of element Metal Metalloid Non-metal Structure Giant metallic lattice
More informationCase Study: The Industrial Manufacture of Ammonia The Haber Process
Case Study: The Industrial Manufacture of Ammonia The Haber Process In the Haber Process, ammonia (NH3) is synthesised from nitrogen and hydrogen gases: N 2 (g) + 3H 2 (g) Ý 2NH3(g), ΔH = 92.4 kjmol -1
More informationF322: Chains, Energy and Resources Rates and Equilibria
F322: Chains, Energy and Resources 2.3.2 Rates and Equilibria 1. Dilute aqueous hydrogen peroxide, H 2 O 2 (aq), is used to sterilise contact lenses. Dilute H 2 O 2 (aq) slowly decomposes at room temperature
More informationUnit-8 Equilibrium. Rate of reaction: Consider the following chemical reactions:
Unit-8 Equilibrium Rate of reaction: Consider the following chemical reactions: 1. The solution of sodium chloride and silver nitrate when mixed, there is an instantaneous formation of a precipitate of
More informationQuestion 8 Chemical properties of metals and nonmetals. 1) magnesium 2) sulfur trioxide 3) iron (II) hydroxide 4) sodium nitrate
Question 8 Chemical properties of metals and nonmetals 1. Calcium oxide doesn t react with 1) NaNO 3 2) HCl 3) CO 2 4) H 2 O 2. Calcium oxide reacts with both of the following 1) SO 2 and O 2 2) H 2 O
More information2. In which of these compounds are there twice as many oxygen atoms as hydrogen atoms? a. H 3 PO 4 c. HClO 3 b. H 2 SO 4 d. H 2 O
Test Review Unit 3_3: Law of conservation of mass Identify the letter of the choice that best completes the statement or answers the question. At the end of the file you can find chemical equations to
More information(i) an element which is gaseous at room temperature and pressure ... [1] (ii) an element which forms an oxide that is a reactant in photosynthesis
1 (a) For each of the following, give the name of an element from Period 2 (lithium to neon), which matches the description. Elements may be used once, more than once or not at all. (i) an element which
More information(b) Describe, and explain, what would happen to the position of the NO 2 /N 2 O 4 equilibrium if the following changes are made
1. Nitrogen dioxide, NO 2, and dinitrogen tetroxide, N 2 O 4, take part in the following equilibrium. 2NO 2 (g) N 2 O 4 (g) ΔH = 58 kj mol 1 (a) State le Chatelier s principle. (b) Describe, and explain,
More informationF321: Atoms, Bonds and Groups Structure & Bonding
F321: Atoms, Bonds and Groups Structure & Bonding 1. This question is about different models of bonding and molecular shapes. Magnesium sulfide shows ionic bonding. What is meant by the term ionic bonding?
More informationCHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS
17 CHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS WHAT IS A CHEMICAL EQUATION? A chemical equation is a way of representing a chemical reaction in symbolic form. For example, when hydrochloric acid
More informationChemistry 40S Chemical Equilibrium (This unit has been adapted from
Chemistry 40S Chemical Equilibrium (This unit has been adapted from https://bblearn.merlin.mb.ca) Name: 1 2 Lesson 1: Defining Equilibrium Goals: Describe physical and chemical equilibrium. Describe the
More informationA-level CHEMISTRY (7405/1)
SPECIMEN MATERIAL A-level CHEMISTRY (7405/1) Paper 1: Inorganic and Physical Chemistry Specimen 2015 Session Time allowed: 2 hours Materials For this paper you must have: the Data Booklet, provided as
More informationWrite a balanced equation for the thermal decomposition of calcium nitrate. ... (2)
1. (a) When solid calcium nitrate is heated, brown fumes of nitrogen dioxide, NO 2, are seen and the solid remaining after decomposition is calcium oxide. Write a balanced equation for the thermal decomposition
More informationDraw one line from each solution to the ph value of the solution. Solution ph value of the solution
1 The ph scale is a measure of the acidity or alkalinity of a solution. (a) Draw one line from each solution to the ph value of the solution. Solution ph value of the solution 5 Acid 7 9 Neutral 11 13
More informationKinetics & Equilibrium Review Packet. Standard Level. 1. Which quantities in the enthalpy level diagram are altered by the use of a catalyst?
Kinetics & Equilibrium Review Packet Standard Level 1. Which quantities in the enthalpy level diagram are altered by the use of a catalyst? Enthalpy I II III Time A. I and II only B. I and III only C.
More informationBalancing Equations Notes
. Unit 9 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written
More informationCHEMICAL REACTIONS. Introduction. Chemical Equations
CHEMICAL REACTIONS Chemistry I Chapter 7 1 Chemical Equations Their Job: Depict the kind of reactants and products and their relative amounts in a reaction. 4 Al (s) + 3 O 2 (g) ---> 2 Al 2 O 3 (s) The
More informationChem!stry. Assignment on Redox
Chem!stry Name: ( ) Class: Date: / / Assignment on Redox Question 1: Which one of the following elements is the most powerful reducing agent? A Aluminium B Copper C Lead D Potassium Question 2: Which of
More informationCalifornia Standards Test (CST) Practice
California Standards Test (CST) Practice 1. Which element has properties most like those of magnesium? (a) calcium (b) potassium (c) cesium (d) sodium 5. Which pair of atoms will share electrons when a
More informationChapter 4. The Major Classes of Chemical Reactions 4-1
Chapter 4 The Major Classes of Chemical Reactions 4-1 The Major Classes of Chemical Reactions 4.1 The Role of Water as a Solvent 4.2 Writing Equations for Aqueous Ionic Reactions 4.3 Precipitation Reactions
More information2017 Version. Chemistry AS C2.6 Chemical Reactivity
2017 Version Chemistry AS 91166 C2.6 Chemical Reactivity Achievement Criteria This achievement standard involves demonstrating understanding of chemical reactivity. Rates of Reaction typically involves:
More informationCHM 111 Final Fall 2012
Name Part I. Multiple Choice 1. Consider the following specific heats of metals. Metal copper cobalt chromium gold silver CHM 111 Final Fall 2012 Specific Heat 0.385 J/(g C) 0.418 J/(g C) 0.447 J/(g C)
More information2. If a gas is released in a reaction (ex: Hydrogen gas bubbles off), is it written as a reactant or a product?
PRE-AP CHEMISTRY SPRING FINAL EXAM REVIEW Name _ Period Exam Date 100% COMPLETION OF THIS REVIEW BY THE DAY OF YOUR FINAL EXAM WILL COUNT AS A 5 POINT BONUS ADDED TO YOUR FINAL EXAM SCORE. THERE WILL BE
More informationRedox. Question Paper. Cambridge International Examinations Chemical Reactions. Score: /43. Percentage: /100
Redox Question Paper Level Subject Exam oard Topic Sub-Topic ooklet O Level hemistry ambridge International Examinations hemical Reactions Redox Question Paper Time llowed: 52 minutes Score: /43 Percentage:
More informationWrite equilibrium law expressions from balanced chemical equations for heterogeneous and homogeneous systems. Include: mass action expression.
Equilibrium 1 UNIT 3: EQUILIBRIUM OUTCOMES All important vocabulary is in Italics and bold. Relate the concept of equilibrium to physical and chemical systems. Include: conditions necessary to achieve
More informationCHEMISTRY. Ions are formed when sulfur dioxide reacts with water. Write an equation for this reaction. SO 2 + H 2 O H + + HSO 3 Allow 2H + + SO 3
Phosphorus(V) oxide is classified as an acidic oxide. Write an equation for its reaction with sodium hydroxide. Ions are formed when sulfur dioxide reacts with water. Write an equation for this reaction.
More informationIdentify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind.
Identify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind. 1. calcium + oxygen 2. cupric carbonate 3. aluminum + hydrochloric
More informationFor the element X in the ionic compound MX, explain the meaning of the term oxidation state.
1. (a) By referring to electrons, explain the meaning of the term oxidising agent.... For the element X in the ionic compound MX, explain the meaning of the term oxidation state.... (c) Complete the table
More informationCHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS
CHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS Answer the following questions as if you were going to hand them in for marking. You will be tested on them in class time. 1) Give the correct chemical
More informationAtoms What subatomic particles make up the atom?
Atoms What subatomic particles make up the atom? What are the masses of the subatomic particles? What do atomic and mass number represent? What does 7 3 Li represent? How are elements arranged in the periodic
More information, are both macromolecules. They have similar physical properties but silicon(iv) oxide is acidic and zirconium(iv) oxide is amphoteric
1 Silicon(IV) oxide, SiO 2, and zirconium(iv) oxide, ZrO 2, are both macromolecules. They have similar physical properties but silicon(iv) oxide is acidic and zirconium(iv) oxide is amphoteric. (a) Defi
More information1 Iodine reacts with chlorine to form dark brown iodine monochloride. I 2 + Cl 2 2ICl
1 Iodine reacts with chlorine to form dark brown iodine monochloride. I 2 + Cl 2 2ICl This reacts with more chlorine to give yellow iodine trichloride. An equilibrium forms between these iodine chlorides.
More informationThe characteristic Properties of Acids and
For more awesome GSE and level resources, visit us at www.savemyexams.co.uk/ The haracteristic Properties of cids and ases Question Paper Level Subject Exam oard Topic Sub-Topic ooklet O Level hemistry
More informationGas Laws. Bonding. Solutions M= moles solute Mass %= mass solute x 100. Acids and Bases. Thermochemistry q = mc T
Name Period Teacher Practice Test: OTHS Academic Chemistry Spring Semester 2017 The exam will have 100 multiple choice questions (1 point each) Formula sheet (see below) and Periodic table will be provided
More information# Ans Workings / Remarks
# Ans Workings / Remarks 1 B Atomic mass and temperature affects the rate of diffusion of gas. The lower the atomic mass, the lighter the substance. The higher the temperature, the higher the rate of collision
More informationLesmahagow High School AHChemistry Inorganic and Physical Chemistry Lesmahagow High School CfE Advanced Higher Chemistry
Lesmahagow High School CfE Advanced Higher Chemistry Unit 1 Inorganic and Physical Chemistry Chemical Equilibrium 1 Dynamic Equilibrium Revision Dynamic equilibrium happens in a closed system when the
More informationACIDS AND BASES 4/19/15. 1) Given the reactions:
NAME: ACIDS AND BASES 4/19/15 ROW PD 1) Given the reactions: (A) NH3(g) + H2O(l) NH4 + + OH (B) HCl + H2O (l) H3O + + Cl As shown in equations (A) and (B) and based on the Bronsted theory, water is an
More informationTypes of Reactions. There are five main types of chemical reactions we will talk about:
Chemical Reactions Types of Reactions There are five main types of chemical reactions we will talk about: 1. Synthesis reactions 2. Decomposition reactions 3. Single displacement reactions 4. Double displacement
More informationBalancing Equations Notes
. Unit 6 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written
More informationBased on the kinetic molecular theory of gases, which one of the following statements is INCORRECT?
1 Based on the kinetic molecular theory of gases, which one of the following statements is INCORRECT? A) The collisions between gas molecules are perfectly elastic. B) At absolute zero, the average kinetic
More informationChapter 11 Practice Test
Chapter 11 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. *You will need your own calculator for blast from the past questions. 1. Some of
More informationSpring Semester Final Exam Study Guide
Honors Chemistry Name Period AlCl3 Cu2S NaCN HI PCl3 CrBr3 Naming and Formula Writing 1. Write the name or formula for each of the following: HClO2 (NH4)2SO4 I4O10 H3N NiN H3PO4 Mercury (II) bromide Phosphorous
More informationChapter Test B. Chapter: Acids and Bases
Assessment Chapter Test B Chapter: Acids and Bases PART I In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. Which of the
More informationAcid, Bases and Salts (IGCSE Chemistry Syllabus )
Acid, Bases and Salts (IGCSE Chemistry Syllabus 2016-2018) Acid o A compound when dissolved in water produces hydrogen ions (H + ) ; proton (H + ) donor o It turns blue damp litmus paper to red o ph 1
More informationUnit Two Worksheet WS DC U2
Unit Two Worksheet WS DC U2 Name Period Short Answer [Writing]. Write skeleton equations representing the following reactions and then balance them. Then identify the reaction type. Include all needed
More information8 Chemical Equations. Flames and sparks result when aluminum foil is dropped into liquid bromine.
8 Chemical Equations Flames and sparks result when aluminum foil is dropped into liquid bromine. Chapter Outline 8.1 The Chemical Equation 8.2 Writing and Balancing Chemical Equations 8.3 Types of Chemical
More information1. The reaction between solid barium hydroxide and solid ammonium chloride can be represented by the equation below.
1. The reaction between solid barium hydroxide and solid ammonium chloride can be represented by the equation below. Ba(OH) 2 (s) + 2NH 4 Cl(s) BaCl 2 (s) + 2NH 3 (g) + 2H 2 O(l) ΔH ο = +51.1 kj mol 1
More informationLISTA DE EXERCÍCIOS AULA 06/10/2016
LISTA DE EXERCÍCIOS AULA 06/10/2016 1- Sodium hypochlorite, the active ingredient in Clorox, can be made by the following reaction: 2 NaOH(aq) + Cl 2 (g) NaCl(aq) + NaClO(aq) + H 2 O(l) If chlorine gas
More informationChemistry Final Exam Sample Items
Chemistry Final Exam Sample Items 1. Which best describes the current atomic theory? a. Atoms consist of electrons circling in definite orbits around a positive nucleus. b. Atoms are composed of electrons
More informationChapter 6. Chemical Reactions. Sodium reacts violently with bromine to form sodium bromide.
Chapter 6 Chemical Reactions Sodium reacts violently with bromine to form sodium bromide. Evidence of Chemical Reactions Chemical Equations Reactants Products Reactant(s): Substance(s) present before the
More informationChemistry Supervised assessment: Equilibrium. Criteria assessed. Assessment instrument. Sample assessment instrument and indicative response
Chemistry 007 Sample assessment instrument and indicative response Supervised assessment: Equilibrium This sample is intended to inform the design of assessment instruments in the senior phase of learning.
More informationChapter 15 Equilibrium
Chapter 15. Chemical Equilibrium Common Student Misconceptions Many students need to see how the numerical problems in this chapter are solved. Students confuse the arrows used for resonance ( )and equilibrium
More informationNATIONAL 5 CHEMISTRY
Farr High School NATIONAL 5 CHEMISTRY Unit 1 Chemical Changes and Structure Question Booklet 1 Rates of Reaction 1. Explain how the following would affect the rate of the reaction between 1.0 g of magnesium
More informationChemistry 101 Chapter 4 STOICHIOMETRY
STOICHIOMETRY Stoichiometry is the quantitative relationship between the reactants and products in a balanced chemical equation. Stoichiometry allows chemists to predict how much of a reactant is necessary
More information5.1 Module 1: Rates, Equilibrium and ph
5.1 Module 1: Rates, Equilibrium and ph 5.1.1 How Fast? The rate of reaction is defined as the change in concentration of a substance in unit time Its usual unit is mol dm 3 s 1 When a graph of concentration
More informationAnswers for UNIT ONE NAT 5 Flash Cards
Answers for UNIT ONE NAT 5 Flash Cards 1. (a) rate increases (b) rate increases (c) rate increases (d) rate increases 2. Average rate = change in property / change in time Where property = concentration,
More informationSCH4U Chemistry Review: Fundamentals
SCH4U Chemistry Review: Fundamentals Particle Theory of Matter Matter is anything that has mass and takes up space. Anything around us and in the entire universe can be classified as either matter or energy.
More informationCHEM111 UNIT 1 MOLES, FORMULAE AND EQUATIONS QUESTIONS
Lesson 1 1. (a) Deduce the number of protons, neutrons and electrons in the following species: (i) 37 Cl - (ii) 1 H + (iii) 45 Sc 3+ (b) Write symbols for the following species: (i) 8 protons, 8 neutrons,
More information(B) K2O potassium dioxide
PRACTICE CHEMISTRY EOC TEST 1. Which substance is a conductor of electricity? (A) NaCl(s) (B) NaCl(l) (C) C6H12O6(s) (D) C6H12O6(l) 2. Which formula is correctly paired with its name? (A) MgCl2 magnesium
More informationMr. Storie 40S Chemistry Student Acid and bases Unit. Acids and Bases
Acids and Bases 1 UNIT 4: ACIDS & BASES OUTCOMES All important vocabulary is in Italics and bold. Outline the historical development of acid base theories. Include: Arrhenius, BronstedLowry, Lewis. Write
More informationH 2 SO 4. HCl. HNO 3 nitric acid. TOPIC: Acids and Bases. e.g. HCl! H + + Cl - sulphuric acid. hydrochloric acid
TOPIC: Acids and Bases Learn these formulae! H 2 SO 4 sulphuric acid HCl hydrochloric acid Acids, especially concentrated acids, are corrosive: you need eye protection and gloves. HNO 3 nitric acid What
More informationChemical Nomenclature Chapter 2.5-8
Chemical Nomenclature Chapter 2.5-8 Octet Rule An octet is 8 valence electrons is associated with the stability of the noble gases does not occur with He, which is stable with two valence electrons (duet)
More informationName: Class: Date: SHORT ANSWER Answer the following questions in the space provided.
CHAPTER 14 REVIEW Acids and Bases SECTION 1 SHORT ANSWER Answer the following questions in the space provided. 1. Name the following compounds as acids: a. H 2 SO 4 b. H 2 SO 3 c. H 2 S d. HClO 4 e. hydrogen
More information3.2.1 Energetics. Enthalpy Change. 263 minutes. 259 marks. Page 1 of 41
..1 Energetics Enthalpy Change 6 minutes 59 marks Page 1 of 41 Q1. (a) Define the term standard molar enthalpy of formation, ΔH f. (b) State Hess s law. (c) Propanone, CO, burns in oxygen as shown by the
More informationCHEMISTRY CP Name: Period:
CHEMISTRY CP Name: Period: CHEMISTRY SPRING FINAL REVIEW SHEET NOTE: Below are concepts that we have covered in class throughout the second semester. Questions are organized by chapter/concept to help
More informationUnit 4. Chemical Calculations
Index Unit 4. Chemical Calculations 1.- Chemical reactions...2 1.1.- What is a chemical reaction?...2 1.2 The law of conservation of mass...2 1.3 Balance of chemical reactions...2 1.4.- Rate of reaction...3
More informationCh 7 Chemical Reactions Study Guide Accelerated Chemistry SCANTRON
Ch 7 Chemical Reactions Study Guide Accelerated Chemistry SCANTRON Name /80 TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. Correct the False statments by changing the
More informationPart 01 - Notes: Reactions & Classification
Objectives: Identify, define, and explain: combination reaction, synthesis reaction, decomposition reaction, single replacement reaction, double replacement reaction, combustion reaction, rapid oxidation,
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The effect of a catalyst on a chemical reaction is to. A) increase the entropy change
More informationAS Paper 1 and 2 Kc and Equilibria
AS Paper 1 and 2 Kc and Equilibria Q1.When one mole of ammonia is heated to a given temperature, 50 per cent of the compound dissociates and the following equilibrium is established. NH 3(g) ½ N 2 (g)
More informationChemistry Review. a) all of the b) a&b c) a,b&c d) a,b&d above
Chemistry Review 1. The elements whose symbols are P, C, and N are (a) potassium, cadmium, and nickel. (b) potassium, carbon, and nitrogen. (c) phosphorus, calcium, and neon. (d) phosphorus, carbon, and
More information(03) WMP/Jun10/CHEM4
Thermodynamics 3 Section A Answer all questions in the spaces provided. 1 A reaction mechanism is a series of steps by which an overall reaction may proceed. The reactions occurring in these steps may
More information6. Which will react faster: Magnesium and 2M hydrochloric acid, or Magnesium and 0.5M hydrochloric acid?
REACTION RATES WORKSHEET WS#1 1. Identify the three components of collision theory. What are the three factors that must be true for a collision to be successful? a. b. c. 2. Do all collisions result in
More information(g) burns according to this reaction? D) CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(l)
Name: 7171-1 - Page 1 1) In a chemical reaction, the difference between the potential energy of the products and the potential energy of the reactants is defined as the A) heat of reaction B) ionization
More information5 Energy from chemicals
5 Energy from chemicals Content 5.1 Enthalpy 5.2 Hydrogen fuel cell Learning Outcomes Candidates should be able to: (a) (b) (c) (d) (e) describe the meaning of enthalpy change in terms of exothermic (H
More information8. The table below describes two different reactions in which Reaction 1 is faster. What accounts for this observation? Reaction 1 Reaction 2.
Public Review - Rates and Equilibrium June 2005 1. What does X represent in the diagram below? (A) activation energy for the forward reaction (B) activation energy for the reverse reaction (C) heat of
More informationAtoms, Elements, Atoms, Elements, Compounds and Mixtures. Compounds and Mixtures. Atoms and the Periodic Table. Atoms and the.
Atoms, Elements, Compounds and Mixtures Explain how fractional distillation can be used to separate a mixture. 1 Atoms, Elements, Compounds and Mixtures Fractional distillation is used to separate components
More informationUnit 4: Reactions and Stoichiometry
Unit 4: Reactions and Stoichiometry Reactions Chemical equation Expression representing a chemical reaction Formulas of reactants on the left side Formulas of products on the right side Arrow(s) connect(s)
More information2. The reaction of carbon monoxide and diiodine pentoxide as represented by the equation
1. The complete combustion of phenylhydrazine, C 6 H 5 NHNH 2, with the oxidizer dinitrogen tetraoxide is shown in the equation C 6 H 5 NHNH 2 + N 2 O 4 CO 2 + H 2 O + N 2 When balanced, the sum of all
More informationBasic SL Concepts. D. 2.0 (Total 1 mark) When the equation above is balanced, what is the coefficient for oxygen? D.
Basic SL Concepts 1. 3.0 dm 3 of sulfur dioxide is reacted with.0 dm 3 of oxygen according to the equation below. SO(g) + O(g) SO3(g) What volume of sulfur trioxide (in dm 3 ) is formed? (Assume the reaction
More information2. Relative molecular mass, M r - The relative molecular mass of a molecule is the average mass of the one molecule when compared with
Chapter 3: Chemical Formulae and Equations 1. Relative atomic mass, A r - The relative atomic mass of an element is the average mass of one atom of an element when compared with mass of an atom of carbon-12
More information6. Which expression correctly describes the equilibrium constant for the following reaction? 4NH 3 (g) + 5O 2 (g) 4NO(g) + 6H 2 O(g)
1. Which of the following can we predict from an equilibrium constant for a reaction? 1. The extent of a reaction 2. Whether the reaction is fast or slow 3. Whether a reaction is exothermic or endothermic
More informationExperiment #4. Chemical Nomenclature
Experiment #4. Chemical Nomenclature Many everyday and historically important chemical compounds have common names. For example, water is the common name for H 2 O, baking soda is the common name for NaHCO
More informationGCE O' LEVEL PURE CHEMISTRY (5073/02) Suggested Answers for 2016 O Level Pure Chemistry Paper 2
Section A (50 M) Aa) trend The number of electron shell increases The number of valence electrons increases Proton number increases There is a change in character from metallic to non-metallic Only true
More informationChemical Reactions Unit
Name: Hour: Teacher: ROZEMA / Chemistry Chemical Reactions Unit 1 P a g e 2 P a g e 3 P a g e 4 P a g e 5 P a g e 6 P a g e Chemistry Balancing Equations Balance the following equations by inserting the
More informationQuestion Bank Ammonia
Question Bank Ammonia 1. Why nitrogenous matter produces ammonia? State a liquid source of ammonia. Ans. When nitrogenous matter (such as animal and vegetable proteins) decays in the absence of air, the
More informationDefinition of Acid. HCl + H 2 O H 3 O + + Cl
Acids Definition of Acid Acids are substances that contain H + ions that ionize when dissolved in water. Arrhenius acid: a compound that increases the concentration of H + ions that are present when added
More informationAdvanced Chemistry Final Review
Advanced Chemistry Final Review 1. What are the products of complete combustion of hydrocarbons? Hydrocarbons are compounds made of carbon and oxygen. When they burn (combine with oxygen) they form carbon
More informationDescribe the structure and bonding in a metallic element. You should include a labelled diagram in your answer. ... [3] ...
3 Gallium is a metallic element in Group III. It has similar properties to aluminium. (a) (i) Describe the structure and bonding in a metallic element. You should include a labelled diagram in your answer.
More informationLe Chatelier's principle
Le Chatelier's principle Any factor that can affect the rate of either the forward or reverse reaction relative to the other can potentially affect the equilibrium position. The following factors can change
More informationAREA 1: WATER. Chapter 6 ACIDS AND BASES. 6.1 Properties of acids and bases
AREA 1: WATER Chapter 6 ACIDS AND BASES 6.1 Properties of acids and bases Acids are: Sour May be corrosive Dissolve in water to produce an electrolyte, Turn blue litmus red Neutralised by bases. Bases
More informationStoichiometry SUPPLEMENTAL PROBLEMS CHAPTER 12. 3Si(s) 2N 2 N 4. (g) 0 Si 3. (s) PO 4. the reaction. Cr(s) H 3. (aq) 0.
CHAPTER 12 Stoichiometry 1. Silicon nitride is used in the manufacturing of high-temperature thermal insulation for heat engines and turbines. It is produced by the following 3Si(s) 2N 2 (g) 0 Si 3 N 4
More information