What is required in order for heat to transfer between two objects & then how does it move

a) two objects need same temperatures, heat travels in both directions
b) two objects need different temperatures, heat travels from the cooler object to the hotter object
c) two objects need different temperatures, heat travels from the hotter object to the cooler object

Two objects at different temperatures are in contact with each other. Heat flows from the warmer to the cooler object until they are both at the same temperature. The answer is C

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).