MAKE-UP 1st 9 weeks Science Review

A CHANGE that alters (changes) the identity of a substance and results in a NEW substance with DIFFERENT properties.

• Chemical Change
• Physical Change

Tags

NGSS.MS-PS1-2

A student has two 100 mL beakers of different clear liquids, both at room temperature. The student mixes them. Which of these reactions would NOT show a chemical change?

• The mixture’s volume is 200 mL.
• The mixture turns blue.
• The mixture heats up.

What is the production of a precipitate?

• formation of solid particles out of a liquid
• formation of liquid drops from a gas
• formation of heat or light from a chemical change

Someone boils water until it evaporates. What kind of change has happened and why?

• physical, because a new substance was not formed
• chemical, because the state of matter changed
• physical, because the identity of the substance was altered

Baking soda and vinegar are mixed,and immediately there are bubbles and fizzing. What does this show?

• formation of a gas
• formation of a precipitate
• formation of a new liquid

A half-eaten apple turns brown. How do we know that this is a chemical change?

• Change in color
• Change in temperature
• Change in state of matter

A student mixes two chemicals and sees the production of bubbles, the formation of a precipitate, a change in shape, and heat being produced.How many of these observations indicate a chemical change?

• 2
• 3
• 4

Someone puts a water bottle in the freezer and it turns to ice. Is this an example of a physical change?

• Yes, because a new substance was not formed.
• Maybe, depending on how long it took for the water to freeze
• No, because a change in state of matter occurred

Which type of change is easier to reverse?

• chemical change
• physical change

A student places a cold ice cube in a glass of water and the ice cube gets warmer. Then she stirs together two room-temperature liquids and the mixture gets very hot. Which one is a chemical change?

• the melting ice cube
• the hot liquid mixture
• neither are chemical changes