Chemical Energy

1. Why does the test tube become warm?

• Hydrogen is produced
• The magnesium neutralises the acid
• the reaction is endothermic
• the reaction is exothermic

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

2.

• A
• B
• C
• D

Tags

NGSS.HS-PS1-4

3.

• only 1
• 2 and 3
• 1 and 3
• only 3

Tags

NGSS.HS-PS1-4

4.

• A
• B
• C
• D

Tags

NGSS.HS-PS1-4

5 Which of the following is true about the formation of bonds between molecules?

• Energy is given off when bonds are formed between molecules.
• Energy is absorbed by the molecule when bonds are formed.
• Energy is neither given off nor absorbed when bonds are formed.

Tags

NGSS.HS-PS1-4

6 Which of the following statement is true about the breaking of bonds between molecules?

• To break a bond between molecules, energy must be released by the molecule
• To break a bond between molecules, no energy is needed.
• To break a bond between molecules, energy must be absorbed by the molecule.

Tags

NGSS.HS-PS1-4

7 Which letter corresponds to the letter of products

• A
• B
• C
• D

Tags

NGSS.HS-PS1-4

8 If ∆H is negative, the reaction is?

• Exothermic
• Endothermic

Tags

NGSS.HS-PS1-4

9 The initial temperature was measured to be 20oC and the final temperature was 10oC. The reaction was

• Endothermic
• Exothermic

Tags

NGSS.HS-PS1-4

10 Which type of reaction is this

• endothermic
• exothermic
• dont know
• none of these

Tags

NGSS.HS-PS1-4