Question

Question
1
Question
2
Question
3
A)
Which type of chemical reaction results in the absorption of energy?
(1 point)
combustion
exothermic
endothermic
replacement
A)
Which type of chemical reaction occurs when natural gas is burned?
(1 point)
endothermic
replacement
exothermic
decomposition
A)
Which part of an energy graph is represented by the highest point?
(1 point)
the activated state
the amount of energy released
the products of the reaction
the amount of energy absorbed
Question
4
Question
5
A)
During photosynthesis, carbon dioxide, water, and energy react to form glucose and oxygen. Whichline would be be longer on the energy graph for photosynthesis?
(1 point)
the horizontal line indicating products
the horizontal line indicating the activated complex
the vertical line indicating bonds forming
the vertical line indicating bonds breaking
A)
The dissolution of calcium chloride in water is given by the following equation:
CaCl
(
s
) + 2H
O → Ca(OH)
(
aq
) + 2HCl(
g
) + heat
How would an energy graph of this reaction appear?
(1 point)
2
2
2
The reactants would appear at a higher energy state than the products.
The reactants and products would appear at a high energy state.
The reactants and products would appear at a low energy state.
The reactants would appear at a lower energy state than the products.

Answer 1

1) endothermic — it absorbs energy.

2) exothermic — burning natural gas (combustion) releases energy.

3) the activated state — the highest point is the transition/activated complex.

4) the vertical line indicating bonds breaking — photosynthesis is endothermic, so more energy is absorbed to break bonds.

5) The reactants would appear at a higher energy state than the products — dissolution of CaCl2 releases heat (exothermic), so products are lower in energy.