Question

which of the following equations are exothermic and endothermic( a) H2o = H2o - 6.0KJ (b) H2 + Cl2 = 2Hcl + 185 KJ (c ) N2 + O2 + 180 KJ = 2No​

Answer 1

(a) It is an endothermic reaction.

(b) It is an exothermic reaction.

(c) It is an endothermic reaction.

• A reaction is said to be endothermic if energy is absorbed in the reaction. It means energy needs to be supplied to the reaction.
• A reaction is exothermic if energy is released at the end of the reaction. Hence, energy is obtained at end of an exothermic reaction.
• If value of energy is positive on reactants side of the equation, it means energy is supplied and reaction is endothermic.
• If value of energy is positive and on the products side, it means energy is obtained and reaction is exothermic.
• In (a) energy is on products side but it is negative. It means that it will be positive if we take it on the reactants side. Hence, it is an endothermic reaction.
• In (b) energy is positive and on products side so it is exothermic reaction.
• In (c) energy is positive and on reactants side. So energy is supplied and reaction is endothermic reaction.

Answer 2

Explanation:

Correct answer is this