Chemistry Reactions Re-test

Is this reaction balanced? If not, select the choice that best explains why it is not balanced.

Mg(NO₃)₂ + 2Na --> 2NaNO₃ + Mg

• No because Mg is not balanced

• No because N is not balanced

• No because Na is not balanced

• No because O is not balanced

• yes

Which coefficient must go in the missing spot to balance the chemical equation?

___Cu + O₂ --> 2Cu₂O

• 4

• 1

• 5

• 3

Balance the following reaction: ___Na + ___O₂ --> ___Na₂O

• 4Na, 2O₂, 3Na₂O

• 2Na, 2O₂, 3Na₂O

• 4Na, O₂, 2Na₂O

• 1Na, O₂, 2Na₂O

What do we call things on the left side of a chemical reaction? For example: 2Na + Cl₂ --> 2NaCl

Na and Cl₂ are on the left side. Again, what do we call these things?

• left elements

• left overs

• products

• reactants

• chemicals

In an exothermic reaction, heat is ...

• taken in
• given out

If a chemical reaction is EXOTHERMIC, the temperature would....

• Stay the same
• Increase
• Decrease

In an endothermic reaction, heat is ...

• taken in

• given out

During an endothermic reaction in a beaker if we are part of the surroundings and touched the beaker, it would feel _______. 

• Warm
• Cold

What type of reaction occurs in a hand warmer?

• exothermic

• endothermic

What is an example of exothermic?

• firework

• ice pack

• coal

• wood