400 Chemistry Problem Set 2
1. Indicate whether each of the following is a pure substance or a mixture and then
for substances either an element or compound and for mixtures either
homogeneous or heterogeneous: fruit salad, table salt, sucrose, prepared instant
lemonade, cobalt, steel, air, and oxygen.
2. Indicate whether each of the following is homogeneous or heterogeneous and then
identify whether each is a pure substance or a mixture: oil and vinegar salad
dressing, an aqueous solution of copper(II) sulfate, copper, pulp-free orange juice,
and water from the ocean.
3. What are the 2 basic types of combinations of matter?
4. Which general type of matter is made up of only one type of atom or molecule?
5. Which general type of matter has properties that change with the proportions of
the substances making it up?
6. Name the 2 types of pure substances.
7. Name the 2 types of mixtures.
8. Which type of matter consists of only one kind of atom?
9. Which type of matter consists of 2 or more different atoms chemically reacted
together?
10. Which type of mixture has its components uniformly distributed throughout?
11. Which type of mixture has components that are not uniformly distributed?
12. Can all pure substances be separated? Explain. If so, how?
13. Can all mixtures be separated? Explain. If so, how?
14. Make a table identifying each of the substances below as pure substances or
mixtures, then classifying them further as either elements, compounds,
homogeneous mixtures, or heterogeneous mixtures: calcium, sodium chloride
(table salt), an apple, plutonium, carbon dioxide, acid rain, polluted air behind a
school bus, paint, ammonia, calcium sulfide, gold, chicken soup, milk, blood, air,
ethanol, tantalum, arsenic, iced tea, silver, fresh squeezed grapefruit juice, sodium
bicarbonate (baking soda), ammonium chloride, spaghetti sauce, methane,
antimony, salad, the atmosphere, carbon monoxide, potassium, chili, and diluted
sulfuric acid.
15. Classify the following materials as elements, compounds, or mixtures: chlorine,
mercury, brass, distilled water, tap water, cigarette tobacco, nylon, dry ice, a
diamond, glucose, and bronze metal.
16. Indicate which of the following properties of sulfur are physical and which are
chemical, and, for the physical properties, identify each one as being either
intensive or extensive: has a density of 2.0 g/mL, yellow color, burns in air with a
blue flame, has a mass of 5 g, does not dissolve in water, brittle solid, is odorless,
is soluble in liquid carbon disulfide, melts at a low temperature when heated,
combines with iron metal to form iron sulfite, reacts with copper metal to form a
black solid, and has a volume of 3.5 cm3.
17. Indicate which of the following properties are physical (include
intensive/extensive) and which are chemical: density, flammability, hardness,
solubility, reacts with acid to form hydrogen gas, blue color, sour taste, high
melting point, supports combustion, reacts with water to form a gas, low boiling
point, can neutralize a base, luster, and odor.
18. Indicate which of the following are physical changes and which are chemical
changes: milk spoiling, rusting iron, cutting paper, making a cloth from cotton,
tarnishing of silver metal, melting butter, fireworks exploding, dissolving sodium
hydroxide pellets in water, reacting hydrochloric acid with potassium hydroxide,
slicing a piece of sodium, heating water and changing it to steam, decomposing
potassium chlorate into potassium chloride and oxygen gas, ice melting, sugar
dissolving in water, wood rotting, pancakes cooking on a griddle, grass growing,
inflating a tire, food digesting, water being absorbed by a paper towel, dynamite
exploding, breaking the windshield of a car, developing photographic film,
combustion of coal in a furnace, excavation of earth, electrolysis of water,
evaporation, expansion of steel metal in a bridge in hot weather, condensation of
water vapor on a mirror, mothballs disappearing over time, erosion of a riverbed,
kicking a football, leaves changing color in the fall, and gallium melting in your
hand.
For additional practice:
Relevant sections in textbook is 1.9
Practice problems are p. 35 (65-70)