The answer would be A: its container.
Gas will expand to fill whatever container it is put in.
The reactant is Mercury (II) Oxide while the products are Mercury and Oxygen separately.
This is because the reactants are typically always on the left side of the yields symbol. In this decomposition reaction, it would still be the same as at the end of the reaction, there were to products produced: Mercury and Oxygen.
Products tend to always be on the right side of the yields symbol, they're what comes out of a reaction no matter what type.
Hope this helps!
Reactions like this one absorb energy because the reactants have less potential energy than the products.
<h3>What is an Endothermic reaction?</h3>
This is the type of reaction in which the reactants absorb heat energy from the surroundings to form products.
This brings about a decrease in the temperature as a result of the reactants having less potential energy than the products thereby making option B the most appropriate choice.
Read more about Endothermic reaction here brainly.com/question/6506846
The formula of chromium fluoride is CFr2.
