Unit 1 Matter Review

Describe the target's accuracy and precision.

• Low accuracy and Low precision

• High accuracy and Low precision

• Low accuracy and High precision

• High accuracy and High precision

Three students weigh a standard mass of 2.0 grams on the same balance. Each person obtains a reading of exactly 7.3 grams for the mass. These results imply that the balance is:

• accurate but not precise

• both accurate and precise

• precise but not accurate

• neither accurate nor precise

Which of the following does not count as evidence of a chemical change when a candle is burning?

• Light is given off in the process

• Soot forms on the bottom of a surface

• Wax melts and vaporizes at the wick

• The flame gives off heat as the candle burns

Three elements, represented by D, E, and Q are located in Period 2. Some properties of these elements are listed in the table above. If a student has small samples of each element, they can be identified most reliably on the basis of:

• Phase

• Mass

• Color

• Density

Which of the models represent a mixture?

• Model 1 only

• Models 1 and 3

• Models 1 and 4

• Models 1, 3, and 4

Which of the following is NOT a physical change?

• Melting a piece of chocolate

• Freezing water into ice cubes

• Mixing sugar and water

• Snapping a glow stick and the color changes

When pipes rust, iron becomes iron oxide. Is rusting a physical or chemical change?

• physical because no new substance forms

• chemical because a new substance forms

Is stretching a rubber band a physical or chemical change?

• physical change because the molecules are just rearranged

• chemical change because new molecules are formed

Figure A represents the molecular structure of a system. After warming it up, it has the structure indicated in Figure B. Is this a physical change or a chemical change?

• physical change because the molecules are only rearranged

• chemical change because bonds are broken and/or formed

Compare 15mL of water in its various states of matter. Which of the following statements is FALSE?

• The particles in solid ice are held in a fixed position.

• Molecules in the liquid state can slide past each other.

• As a gas, kinetic energy of the particles is highest.

• As a solid, the particles will occupy the entire volume of the container.