Unit 1 States of Matter

The diagram represents a phase change for some copper. Which of the following phase changes are the copper atoms undergoing?

• gas to liquid

• liquid to gas

• solid to liquid

• liquid to solid

The heating curve shows how a substance changed phase as temperature increased over time. Which points on the graph indicate the substance absorbing energy and undergoing a phase change?

• A, C, and E

• B and D

• C

• A, B, D, and E

What happens when a substance undergoes a phase change?

• The temperature increases.

• The temperature decreases.

• The temperature remains constant.

• The temperature changes by 100 degrees Celsius.

A sample of gas is in a cylinder as shown. If the temperature is kept constant and the piston moves down to decrease the volume, the pressure increases because the gas particles...

• expand.

• lose velocity within the container.

• become smaller.

• collide more frequently with the container.

Which list shows phases of matter from particles that are MOST energized to particles that are LEAST energized?

• solid, liquid, gas, plasma

• gas, plasma, liquid, solid

• liquid, solid, plasma, gas

• plasma, gas, liquid, solid

The circles in the boxes shown above represent the particles of a material in its three phases. From left to right these are

• solid, gas and liquid.

• solid, liquid, and gas.

• gas, liquid, and solid.

• liquid, solid, and gas.

This graph shows temperature vs. energy data for a substance. What is the boiling point of this substance?

• 0 degrees Celsius

• 20 degrees Celsius

• 50 degrees Celsius

• 90 degrees Celsius

The graph shows a phase change diagram. Which segments indicate an absorption of energy and a phase change taking place?

• AB and BC

• AB and CD

• BC and CD

• CD and DE

This graph represents a heating curve of a substance. Which region on the graph represents a solid phase?

• I

• II

• III

• IV

Grace observed 50mL of a clear substance. She poured it from a cup into a bag and noticed that it flowed, and took the shape of the container, but the volume did not change. She then poured it into a container shaped like a box and noticed that again, it flowed and took the shape of the new container, but its volume remained the same. What state of matter was the substance that Grace was observing?

• solid

• liquid

• gas

• plasma