Chemistry Unit Learning Check

Melting wax is this an example of a physical change.

• True
• False

Burning wood is this an example of a physical change.

• True
• False

What do we call the temperature at which a solid turns into a liquid?

• Freezing point
• Melting point
• Boiling point
• Condensation point

What is the amount of matter in a given space or volume?

• Specific gravity
• Weight
• Ionization
• Density

Object A has a mass of 50 g.  Object B has a mass of 60 g.  Both objects are the same size.  Which one has more density?

• Object A
• Object B
• They are equal.
• You cannot determine this.

3.Objects that are more dense than water will ____ in it.

• Float
• Sink
• Hover in the middle
• Dissolve

A rock has a mass of 24 g and a volume of 6 mL.  What is the density?

• 3 g/mL
• 5 g/mL
• 4 g/mL
• 6 g/mL

What is the density of an object with a mass of 25 g, a length of 5 cm, width of 1 cm and height of 1 cm?

• 3 g/mL
• 5 g/mL
• 4 g/mL
• 6 g/mL

A graduated cylinder has 50 mL of water.  When a rock is dropped into the cylinder, the water rose to 53 mL.  The rock has a mass of 18 g.  What is its density?

• 3 g/mL
• 6 g/mL
• 0.36 g/mL
• 54 g/mL

Which of the following is evidence of a chemical reaction?

• Boiling
• Condensation
• Temperature change
• Evaporation