HOW WILL WE GET TO KNOW WHETHER THE HEAT IS EVOLVED OR ABSORBED IF WE HAVE GIVEN A WORD EQUATION AND WE HAVE TO WRITE IT IN SYMBOLIC?

Asked by Hitesh Suthar | 23rd Jun, 2014, 09:33: AM

Expert Answer:

Consider the two reactions given below:

KNO3(s) + H2O(l) + Heat → KNO3(aq)

NaOH(s) + H2O(l) → NaOH(aq) + Heat

In the reaction of KNO3, there is absorption of heat and so the temperature of the reaction falls. Such reactions accompanied by absorption of heat are called endothermic reactions.

In the second reaction NaOH dissolves in water and there is evolution of heat leading to the rise in temperature. Reactions where heat is evolved are called exothermic reactions.

Answered by Vaibhav Chavan | 23rd Jun, 2014, 12:05: PM