Chemistry: The Science of Matter Ch 1
Chemistry Science that investigates & explains the structure and properties of matter Matter Anything that takes up space and has mass Mass Amount of matter that an object contains (Weight is the force of gravity on the mass)
States of matter Solid Liquid Gas
Solid Particles are tightly packed usually in a regular arrangment Particles vibrate (jiggle) but do not move past each other Not easily compressed Fixed volume and fixed shape
Liquid Particles close together with no regular arrangement Particles vibrate, move past each other by sliding Not easily compressed Assumes shape of container, fixed volume
Gas Particles separate with no regular arrangement Particles vibrate and move freely Easily compressed Assumes shape and volume of container
What is not matter? A. Water B. Heat C. Salt D. Hair
What is matter? A. Radio Waves B. Aspirin C. Light D. Magnetic Fields
What is matter made of? It is a pure SUBSTANCE OR It is a MIXTURE
A Pure Substance A sample of matter that has the same fixed composition and definite physical and chemical properties
A Substance can be a Compound Or a Element
An Element is a substance Cannot be broken down into simpler substances Simplest form and basic building block of matter 118 Elements 90 naturally occurring (All in first 92 except 43-Technetium and 61-Promethium) Found on The Periodic Table Each element has a symbol
A Compound is a substance Can be broken down into simpler substances Chemical combination of two or more different elements joined together in fixed proportions The relative amounts of the elements never change in a compound Properties of compounds are different from the properties of the elements that compose the compound More than 10 million compounds
A compound has a Chemical Formula Combination of chemical symbols that show what elements make up a compound and the number of atoms of each element
Element!!! Name the element or symbol
IRON A. Ir B.Fe C. I
Hydrogen A.Hg B.H C.Hy
Na A.Sodium B.Naturium C.Rhodium
Hg A.Helligrium B.Mercury C.Antimony
Pure Substance Is it an Element or a Compound??
Fe A. Element B. Compound
H2O A. Element B. Compound
NaCl A. Element B. Compound
Carbon A. Element B. Compound
Silver Nitrate A. Element B. Compound
Hydrochloric Acid A. Element B. Compound
Chemical Formula of a Compound Count the number of atoms
H20 How many atoms of Oxygen (O)? A. 0 B. 1 C. 2 D. 3
H20 How many atoms of Hydrogen (H)? A. 0 B. 1 C. 2 D. 3
K2C4H4O6 How many atoms of carbon (C)? A. 1 B. 2 C. 4 D. 6
Mg(OH)2 How many atoms of Hydrogen (H)? A. 0 B. 1 C. 2 D. 3
Mg(OH)2 How many atoms of Oxygen (O)? A. 0 B. 1 C. 2 D. 3
H2(SO)4 How many atoms of Sulfur (S)? A. 0 B. 1 C. 2 D. 4
A Mixture Pure substances that exist together without chemically combining Retains the properties of each of its components It does not have fixed compositions-relative amounts of each pure substance can vary The basic identity of each substance is not changed It can be separated by physical processes
Two types of Mixtures Heterogeneous-different composition throughout Hetero--different Homogeneous-same composition throughout Homo the same Also called a solution May look like a pure substance but can vary (tea with a little sugar or tea with lots of sugar)
A Solution is a homogeneous mixture Examples Gas in gas air Gas in liquid soda Liquid in liquid antifreeze Solid in liquid seawater Solid in solid - brass (An alloy is a solid homogeneous mixture) Solute-the substance being dissolved Solvent-the substance that dissolves the solute Aqueous solution -solvent is water
Homogeneous Mixture Solution Mixture with particle size 0.1-2 nanometers Particles are at the molecule or ion level May have a color but will be transparent (can see through) Light passes through with no scattering of light Cannot be separated by filtration, may be separated by distillation Examples air with no clouds, vinegar, oil, sugar and water mixture
Heterogeneous Mixture?? Colloid (also know as colloidal dispersions) Particle size greater between 2 and 1000 nanometers Particles consist of clumps of molecules Particles are usually not visible to the naked eye Particles large enough to scatter light (Tyndall effect) Looks homogeneous to the naked eye Do not separate upon standing Cannot be separated by filtration May appear murky or opaque Might be separated by a centrifuge or a semipermeable membrane Types Gel liquid in a solid (jelly, stick deodorant) Emulsion two liquids (milk, mayonnaise) Aerosol solid or liquid in a gas (fog, smoke)
Heterogeneous Mixture Suspension Particle size greater than 1000 nanometers Particles are visible to the naked eye Murky or opaque Settle upon standing Does not transmit light Can be separated by filtration
What type of mixture?
Orange juice (with lots of pulp) A. Homogeneous B. Heterogeneous
Vegetable Soup A.Homogeneous B.Heterogeneous
Homo- means A. Same B. Different
Diet Coke A. Homogeneous B. Heterogeneous
Air A. Homogeneous B. Heterogeneous
Is it a Substance or a Mixture?
Iron A. Substance B. Mixture
Sand mixed with sugar A. Substance B. Mixture
Water A. Substance B. Mixture
Air A. Substance B. Mixture
Blood A. Substance B. Mixture
Properties of Matter
Properties of Matter Intensive or Extensive Intensive Properties that do not depend on the amount of matter present (independent of the mass) Color Odor Luster shiny Malleability ability to beat into thin sheets Ductility ability to be drawn into thin wires Conductivity ability of a substance to allow the flow of electricity Hardness how easily it can be scratched Melting or Freezing Point Boiling Point Density Solubility
Properties of Matter Intensive or Extensive Extensive Properties that do depend on the amount of matter present Mass Weight Volume Length
Properties of Matter Can be QUALITATIVE No measurement necessary (Quality) The solid is hard. Can be QUANTITATIVE Uses measurement (Quantity) Iron has a density of 7.86 g/ml.
o The temperature is 98 F A. Qualitative B. Quantitative
Sucrose is composed of C, H, & O A. Qualitative B. Quantitative
The sky is blue. A. Qualitative B. Quantitative
I weight 99 pounds. A. Qualitative B. Quantitative
??????? What are some properties that might be used to identify matter?
??????????????????? Color Solid, liquid, gas Does it burn? Does it dissolve in water? What happens when you mix it with?
Physical Properties Characteristics that matter exhibits without any change in its identity Solubility (dissolves) Physical State (solid, liquid, gas) Temperature at which it changes from one state to another (Melting Point, Boiling point) Color Density (mass/volume) Electrical Conductivity Odor Viscosity (how easily it flows)
Physical Changes Change in matter that does not involve a change in the identity of individual substances You can separate a mixture using Physical Changes The same compounds are present before and after the physical change
Examples of Physical Changes Boiling Freezing Melting Subliming Evaporating Dissolving Mixing Condensation Precipitation
How can you separate sugar and sand using physical changes?
Chemical Properties Can only be observed when there is a change in the composition of the substance Describes the ability of a substance to react with other substances or decompose
Chemical Properties Can only be observed when there is a change in the composition of the substance Describes the potential or ability of a substance to undergo a chemical change
Chemical properties Rusts No reaction Prevents oxidation Breaks down in light Formation of gases Evolution of light and heat Absorption of energy Flammability Radioactivity Sensitivity to light Toxicity
Chemical Change (Chemical Reaction) The change of one or more substances into other substances Involves a rearrangement of the atoms Involves some sort of energy change
Clues that a chemical change has occurred 1. Gas is produced 2. Light is produced Lead nitrate + potassium iodide lead iodide (ppt) + potassium nitrate 5. Precipitate formed Calcium + hydrochloric acid calcium chloride + hydrogen gas 4. Color change (not normal!) Magnesium + oxygen 3. Temperature change CO2 flame is extinguished! O2 flame is reignited H2 pop See above 6. Odor changes Barium hydroxide + ammonium chloride ammonium hydroxide and barium chloride
Energy changes Exothermic Give off heat energy (feels hot) Dynamite-explosion of nitroglycerin Endothermic Absorb heat energy (feels cold) photosynthesis
Burning a log A. Exothermic B. Endothermic
Law of conservation of Mass In a chemical change, matter is neither created nor destroyed Atoms do not disappear The amount of mass at the beginning of the chemical change must equal the amount of mass at the end of the chemical change
In the procedure shown above, a calcium chloride solution is mixed with a sodium sulfate solution to create the products shown. Which of the following is illustrated by this activity? F The law of conservation of mass G The theory of thermal equilibrium H The law of conservation of momentum J The theory of covalent bonding
When 50 ml of isopropyl alcohol (39.5 g) is added to 50 ml of water (50 g), the mixture will have a volume of 98 ml. What is the mass in grams of this mixture? Record and bubble in your answer to the nearest tenth on the answer document.
After the reaction was complete, the unreacted sulfur was removed. The table contains the results of the investigation. How much sulfur, in grams, failed to react with the copper? Record and bubble in your answer to the nearest hundredth on the answer document. Copper (Cu) and sulfur (S) were heated in a covered container. After the reaction was complete, the unreacted sulfur was removed. The table contains the results of the investigation. How much sulfur, in grams, failed to react with the copper? Record and bubble in your answer to the nearest hundredth on the answer document.
If all the reactants in a chemical reaction are completely used, which of the following statements accurately describes the relationship between the reactants and the products? F The products must have a different physical state than the reactants. G The total mass of the reactants must equal the total mass of the products. H The reactants must contain more complex molecules than the products do. J The density of the reactants must equal the density of the products.
When 127 g of copper reacts with 32 g of oxygen gas to form copper (II) oxide, no copper or oxygen is left over. How much copper (II) oxide is produced? F 32 g G 95 g H 127 g
According to the law of conservation of mass, how much zinc was present in the zinc carbonate? A 40 g B 88 g C 104 g D 256 g
Physical or Chemical property??
Baking Soda is a white powder A. Physical property B. Chemical property
Fluorine is a highly reactive element. A. Physical property B. Chemical property
Aluminum bends easily A. Physical property B. Chemical property
Physical or Chemical Change?
A pan of water boils on the stove. A. Physical change B. Chemical change
A match lights when struck. A. Physical change B. Chemical change
Ice cream melts A.Physical Change B.B. Chemical Change
Sodium reacts with water A.Physical Change B.Chemical Change
Baking soda bubbles and gives off carbon dioxide when it is moistened A. Physical change B. Chemical change
Change from solid to liquid & from gas to liquid A.Physical Change B.Chemical Change
Squeeze a HOT HANDS and the pad warms up. A. Physical change B. Chemical change
A lump of gold is pounded into a large, thin sheet. A. Physical change B. Chemical change
Air is squeezed by a pump and forced into a tire. A. Physical change B. Chemical change
Disgestion-Physical or Chemical? Physical Chewing breaks food into smaller pieces
Digestion-Physical or Chemical Chemical Large molecules (like starch and proteins) are changed into simple sugars and amino acids Enzymes like pepsin and amylase help
Oxidation-Physical or Chemical? Chemical Example when iron and oxygen form a new substance--rust
The Rock Cycle-Physical or Chemical?
Rock Cycle Sediments are deposited-physical Sediments (under pressure) turn into sedimentary rocks-physical Sedimentary rocks (under heat and pressure) turn into metamorphic rocks- Chemical Metamorphic rocks melt into magma-physical & Chemical Magma cools and forms new rock with new minerals-physical & Chemical