A sample of 52.0 g of neon gas is placed in a balloon with a volume of 10.3 L at 25.0 °C. If 34.2 g of neon is then added to the balloon at constant temperature and pressure, what would be the new volume of this balloon?

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.

what is the question here. i think you messed up.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.