Question

which among the following is an exothermic reaction a. 2SO3-------2SO2+O2. b. Li2CO3--------LiO +CO2 c. 2H2+O2--------2H2O d. 2HgO--------2Hg+ O2​

Answer 1

thanks so much for your quick reply and the kids will be in town and I have a meeting at my house

Answer 2

Answer: $2H_2+O_2\rightarrow 2H_2O$

Explanation:

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and $\Delta H$ for the reaction comes out to be positive.

All decomposition reactions are endothermic reactions as energy is absorbed to break the bonds.

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and $\Delta H$ for the reaction comes out to be negative.

Synthesis reaction is exothermic as bonds are formed and energy is released.

a. 2SO_3\rightarrow 2SO_2+O_2[/tex] : Endothermic

b. $Li_2CO_3\rightarrow LiO+CO_2$: Endothermic

c. $2H_2+O_2\rightarrow 2H_2O$ : Exothermic

d. $2HgO\rightarrow 2Hg+O_2​$: Endothermic