Chemical changes

Which of the following is a sign that a chemical reaction has occurred?

• change in shape
• melting
• formation of a gas
• dissolving

Tags

NGSS.MS-PS1-2

Which of these is a result of a chemical change?

• A mixture
• A solution
• A new substance
• Melting or freezing

Tags

NGSS.MS-PS1-2

Which of the following is a sign that a physical change has occurred?

• Bubbles forming

• The object being broken into smaller pieces

• Heat being produced

• Light being produced

The left side of the equation below is called

• Products
• Reactants

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

What does the Law of Conservation of Mass state?

• Matter cannot be gained or lost in a chemical reaction.
• Matter can only be lost in a chemical reaction.
• Matter can only be gained in a chemical reaction.
• Matter can be gained and lost in a chemical reaction. 

Tags

NGSS.MS-PS1-5

Some hydrochloric acid is added to marble chips in a test tube. The students observed bubbles and fizzing. The gas is ....

• Oxygen gas 
• Carbon dioxide 
• Hydrogen gas 
• nitrogen gas 

Tags

NGSS.MS-PS1-2

In the above reaction, to test for the gas I could ...

• Bubble it through limewater and it will go milky 
• do the pop test and it will burn 
• Light a taper and it will burn brighter
• note the colour change to yellow 

In another reaction, the student places a piece of metal into a test tube and adds an acid again. Its fizzes ..
The gas produced is called...

• nitrogen 
• Oxygen gas
• sulphur dioxide 
• Hydrogen gas 

The process going from a gas to a liquid is called ...

• evaporation 
• melting 
• condensation 
• sublimation 

Finish of the following word equation 
Copper carbonate + hydrochloric acid = Carbon Dioxide + copper chloride + ______.

• water
• Hydrogen gas 
• copper 
• oxygen