Question

Many chemical reactions produce heat. Select the explaination that correctly describes where the heat energy comes from. are either of these right?

A The heat energy in chemical reactions always comes from another heat source because heat energy can never be converted to or from other energy types.

B Chemical reactions can change chemical energy into heat energy.

Answer 1

if the reaction "produces" heat, then the system/reaction is releasing heat to the surroundings

A The heat energy in chemical reactions always comes from another heat source because heat energy can never be converted to or from other energy types. false, it can be converted from chemical energy ( i.e. internal energy of chemical bonds)

B Chemical reactions can change chemical energy into heat energy. True, the chemical bond ocntains energy, when reacting, they are broken/formed, the overall balance is the heat being released in this case