That would be an endothermic reaction! :)
Number 1: (A.)
Number 2: (A.)
Number 3: (B.)
I'm probably wrong but that is what i think
One of the two products of this reaction is carbonic acid (H2CO3), which immediately forms water and the gas you identified after exposure to the flaming and glowing splints. Write a balanced equation showing the decomposition of carbonic acid.
