Which of the following choices would have a negative entropy change? A. CaCO3(s)−>CaO(s)+CO2(g)

N2(g) + 3H2(g)- >2NH3(g) denotes a negative entropy change.

Explanation:

Entropy is defined as the extent of disorder in a system. The degree of entropy is more in a gas and less in a solid.

Here, 1st reaction produces ammonia from nitrogen and hydrogen. We can see that four moles of gases produces 2 moles of gaseous product. So the degree of disorder in the system is decreasing. So the entropy is also decreasing.

i think its 100

i hope this !