GCSE Chemistry 3 Summary Questions

Transcription

1 GCSE Chemistry 3 Summary Questions Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 C3.1.1 The early Periodic table (p73) Explain Newlands law of Octaves. Explain why Newlands law was criticised. Explain why Mendeleev was much more successful than Newlands. C3.1.2 The modern Periodic table (p74) How are the elements in the Periodic table arranged? How are the electrons in an atom set out? What is the group number equal to? What is the period number? C3.1.3 Trends within the Periodic table (p75-p77) As you go down Group 1, what is the trend in reactivity? What properties do Group 1 elements have in common? Explain why there is an increase in reactivity going down Group 1. [H] As you go down Group 7, what is the trend in reactivity? What properties do Group 7 elements have in common? Explain why there is an decrease in reactivity going down Group 7. [H] What are halides? The halogens are all non-metals with coloured vapours. Describe the colour of each of the following and state how reactive they are. (a) Fluorine (b) Chlorine (c) Bromine (d) Iodine Fill in the blank: A more reactive halogen can a less reactive halogen from an aqueous solution of its salt. Describe the properties of transition metals. What colours do the transition compounds have: (a) Potassium chromate (b) Potassium manganite (c) Copper (II) sulphate Explain how Iron, Manganese oxide and Nickel are useful as catalysts. Page 1 of 9

2 Q20 Q21 Q22 Q23 Q24 Q25 Q26 Q27 Q28 Q29 Q30 Q31 Q32 Q33 Q34 Q35 Q36 Q37 C3.2.1 Hard and soft water (p78 and p79) What can soft water form? What can hard water form? Which dissolved substances does hard water contain? What are the advantages of hard water? What are the disadvantages of hard water? What is the difference between temporary hard water and permanent hard water? What causes temporary hard water to be softened by boiling? Which compound decomposes within temporary hard water? [H] Why does using hard water increase costs? What causes the efficiency of heating systems and kettles to be reduced when hard water is heated in kettles? Write down the word equation that demonstrates the formation of calcium hydrogencarbonate. Hard water can be made soft by removing the dissolved calcium and magnesium ions. Describe the TWO methods in which this can be done. C3.2.2 Purifying water (p80) Fill in the blanks: Water of the correct quality is essential for life. For humans, drinking water should have sufficiently levels of and. In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Explain the stages needed in order to make water clean to drink. (6 marks) Discuss the advantages and disadvantages of adding chlorine and fluoride to drinking water. How does an ion exchange work? How can totally pure water be produced and what can it be used for? What are the disadvantages of producing drinking water by distillation? In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Explain how you would carry out titration to compare the hardness of water samples. (6 marks) Page 2 of 9

3 Q38 Q39 Q40 Q41 Q42 Q43 Q44 Q45 Q46 C3.3.1 Energy from reactions (p89-p92) Explain how fuel energy is calculated using a calorimeter. Describe how you would carry out the energy changes for neutralisation reactions or for reactions of solids with water. What formula can used to calculate the amount of energy transferred during a chemical reaction? You must state the meaning of the letter and the unit(s) used. 50 cm 3 of an acid was added to 50 cm 3 of an alkali. The mixture was stirred and the temperature increased from 18 C to 28 C. What was the amount of energy released in J? (3 marks) In an experiment, Ethanol was burnt from a spirit burner and the energy released was used to heat 50 g of water. The starting temperature of the water was 19 C but by the end of the reaction, the temperature had risen to 41 C. The mass of fuel in the spirit burner was initially 40.0 g, but this had decreased to 38.5 g by the end of the reaction. Calculate the energy change in kj/g of fuel. (5 marks) What happens to the bonds of both products and reactants during a chemical reaction? What is an exothermic reaction? Do products have more or less energy than reactants in exothermic reactions? What is an endothermic reaction? Do products have more or less energy than reactants in endothermic reactions? Label the energy level diagram of Figure 1, an exothermic reaction and Figure 2, an endothermic reaction. Page 3 of 9

4 Q47 Figure 1 Figure 2 Q48 Q49 Q50 Q51 Q52 Q53 Q54 Figure 3 Label Figure 3, showing the energy changes in chemical reactions. Study Figure 3. Explain what is meant by number 1 on the diagram. Draw Figure 3 and show on the diagram how a catalyst may have an effect. Describe the advantages of lowering the activation energy. Complete questions 4 and 5 on page 126 in the CGP GCSE Chemistry Workbook. Describe the TWO ways in which Hydrogen is used to power cars. Discuss the advantages and disadvantages of Hydrogen as a fuel. Evaluate the use of fuel cells. Page 4 of 9

5 Q55 Q56 Q57 Q58 Q59 Q60 Q61 Q61 Q62 Q63 C3.4.1 Analysing substances (p93 and p94, p87 and p88) Complete the table below showing the metal ion and the colour the flame goes. METAL ION FLAME COLOUR Lithium Sodium Potassium Calcium Barium Complete the table below showing the metals ions and the colour the precipitate goes with sodium hydroxide solution. METAL ION PRECIPITATE COLOUR Calcium, Ca 2+ Copper(II), Cu 2+ Iron(II), Fe 2+ Iron(III), Fe 3+ Aluminium, Al 3+ Magnesium, Mg 2+ Describe the test for carbonate ions. This question is about halide ions. How would you test for chloride, bromide or iodide ions? Complete the table, which HALIDE ION PRECIPITATE FORMED COLOUR OF PRECIPITATE shows the Chloride, Cl precipitate Bromide, Br formed and the Iodide, I colour of precipitate of the halide ions. Describe the test for sulphate ions. Describe what a titration is. In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Describe how a titration experiment is carried out. (6 marks) What formula is used to calculate the concentration in moles per dm 3? State the units. [H] What formula is used to calculate the concentration in grams per dm 3? State the units. [H] Page 5 of 9

6 Q64 Q65 Q66 C3.5.1 Making Ammonia (p81 and p82) How is Ammonia produced? Describe how Nitrogen and Hydrogen are obtained. Label the letters on Figure 4 of the Haber process. Q67 Q68 Q69 Q70 Q71 figure 4 In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Explain what is happening at each stage of the Haber process. Use the numbers on figure 4 to help you. (6 marks) What is a closed system? [H] When a reversible reaction occurs in a closed system, what is reached? [H] What do the relative amounts of all the reacting substances at equilibrium depend on? [H] Fill in the blanks: In a reversible reaction the position of equilibrium depends very strongly on the and surrounding the reaction. [H] Page 6 of 9

7 Q72 Q73 Q74 Q75 Q76 Q77 Q78 Q79 What happens when the temperature increases in a reversible reaction? [H] What happens when the temperature decreases in a reversible reaction? [H] What happens when the pressure is raised in a reversible reaction? [H] What happens when the pressure is lowered in a reversible reaction? [H] Explain why adding a catalyst would not affect the equilibrium position. [H] Evaluate the conditions used in industrial processes in terms of energy requirements. Describe the conditions used in the manufacture of Ammonia to increase the rate of reaction. (4 marks) Describe and explain the conditions used in the manufacture of Ammonia to increase the yield. (7 marks) Page 7 of 9

8 Q80 Q81 Q82 Q83 Q84 Q85 Q86 Q87 Q88 Q89 Q90 Q91 Q92 Q93 Q94 C3.6.1 Alcohols (p83) What are alcohols? What is the general formula for an alcohol? What properties do the first three alcohols share? What is Methylated spirit and describe its use? State the formula and draw the structures for the three alcohols. C3.6.2 Carboxylic acids (p84) What are Carboxylic acids? What functional group do Carboxylic acids share? What do the names of Carboxylic acids end in? Complete the table below: CARBOXYLIC ACID NUMBER OF C ATOMS Methanoic acid Ethanoic acid Propanoic acid STRUCTUAL FORMULA DISPLAYED FORMULA Complete the following reaction: Ethanoic acid + Sodium carbonate + What is vinegar? How is Ethanoic acid formed? How is the formation of Ethanoic acid achieved? Describe the properties of Carboxylic acids. [H] How are Carboxylic acids useful in industry? Page 8 of 9

9 C3.6.3 Esters (p85) Q95 What are Esters? What functional group do Esters share? Q96 What properties do Esters have in common? Q97 How do the properties of Esters make them useful in the industry? Q98 How is Ethyl ethanoate made? Q99 What products are formed when Ethanol reacts with Ethanoic acid? Q100 What products are formed when Ethanol reacts with Ethanoic acid? This time, write a balanced symbol equation. Q101 Using your answer to Q100, draw the structural formula for each one. Q102 Complete the table below: Name of alcohol Name of carboxylic acid Name of ester Ethanol Propanoic acid Butanol Methanoic acid Pentanol Ethanoic acid Page 9 of 9