During a chemical reaction, what remains constant?

composition

temperature

energy

bonds

According to the first law of thermodynamic, which states that energy can neither be created nor destroyed, the energy content of a chemical reaction will always be constant. Thus, during chemical reaction energy remains constant.

Ithink its solid. hope this

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.