1. which of the following should be classified as a suspension?
A. soda**
B. sand in water
C. glass
D. milk
2. Which of the following is an of example of a chemical property?
A. density
B. flammability
C. hardness**
D. melting point
3. Which state of matter has a definite volume but a variable shape?
A. solid
B. liquid
C. gas
D. vapor**
4. Evaporation is the phase change in which a substance changes from
A. a solid to a gas
B. a solid to a liquid
C. a gas to a liquid **
D. a liquid to a gas
5. A(n)____ change occurred when a metal changed color because it reacted with another substance
A. physical**
B. condensation
C. chemical
D. evaporation
6. Boyle's law relates volume and
A. temperature
B. number of particles**
C. pressure
D. mass
7. All pure substances
A. contain only one type of atom
B. can be broken down into simpler substances
C. cannot be broken down into simpler substances**
D. have a fixed composition
8. At room temperature (21'C), a substance with melting point of 40'C is a
A. solid
B. liquid**
C. gas
D. mixture
9. Formation of a precipitate is usually evidence
A. the separation of a mixture
B. a chemical change
C. the formation of a mixture
D. a physical change**
10. If a solid piece of iron is heated and remains at 80'C until it is completely melted, you know that 80'C is
A. the freezing point of iron
B. the melting point of iron**
C. the boiling point of iron
D. both the freezing and melting points of iron.
11. Which of the diagrams could represent an element?
A. drawing I
B. drawing II
C. drawing III**
D. drawings I and III
12. Which of the drawings could represent a homogeneous mixture?
A. drawing I**
B. drawing II
C. drawing III
D. drawings I and III
13. Which statement best explains what must take place for water to boil?
A the water releases energy to its surroundings
B. bubbles rise to the surface of the water
C. the vapor pressure of the water becomes equal to the atmospheric pressure
D. the temperature of the water increases**
14. Which of the phase changes does NOT involve changing a liquid into a gas?
A. sublimation**
B. vaporization
C. evaporation
D. boiling
15. During an endothermic phase change,
A. the temperature of a substance rises
B. the temperature of a substance stays the same
C. energy is transferred from a substance to its surroundings**
D. a substance absorbs energy from its surroundings
16. If the speed of an object increases, its kinetic energy
A. decreases**
B. increases
C. stays the same
D. is unpredictable
HELP PLEASE!!!!
1 answer