Chemistry Sem 1 Unit 1 The Study of Chemistry

Which answer is an example of a chemical property?

• ability to become magnetic

• ability to conduct electricity

• ability to conduct heat

• ability to react with acid

You run a chromatogram of inks belonging to three crime suspects and from a ransom note. The inks resolve into the following numbers of spots: suspect A = 2, suspect B = 4, suspect C = 2, note = 4.

Which suspect would you most likely bring in for questioning?

• suspect A

• suspect B

• suspect C

• none of the suspects

Which example is a homogenous mixture of two or more pure substances?

• water

• coffee

• alcohol

• mercury

Which procedure involves a physical change in one of the substances?

• creating salt by reacting sodium metal and chlorine gas

• allowing a nail to rust

• building a model rocket propelled by mixing baking soda and vinegar

• grinding chalk into a fine powder

You heat two substances, A and B. Both substances change color. When cooled, substance A returns to its original color, but substance B does not.

What most likely happened in this situation?

• A physical change occurred in both substances.

• A physical change occurred in substance A, and a chemical change occurred in substance B.

• A chemical change occurred in substance A, and a physical change occurred in substance B.

• A chemical change occurred in both substances.

How many grams are in a 5 pound sample?

Express your answer in scientific notation with two significant figures.

(1 pound=453.592 grams)

• 2.26 × 10² g

• 2.268 × 10³ g

• 1.1 x 10⁴ g

• 2.3 × 10³ g

Jim, Jane, Ann, and Bill measure an object's length, density, mass, and volume, respectively.

Which student's measurement might be in kilograms?

• Jim's

• Jane's

• Ann's

• Bill's

How many centimeters are in 0.05 kilometers?

• 50

• 500

• 5,000

• 50,000

A chemical reaction gives off 2,100 kJ of heat energy.

About how many calories is it equal to?

(1 calorie=4.18 Joules)

• 5.0 × 10³ calories

• 5.0×10⁴ calories

• 5.0×10⁵ calories

• 5.0×10⁶ calories

What goes on the y-axis of a graph?

• dependent variable values

• independent variable values

• graph title

• trend line