Question

Which of the following processes are endothermic? Which of the following processes are endothermic? the reaction associated with the ionization energy of potassium. the reaction associated with the heat of formation of CaS. the formation of F2 from its elements in their standard states. the reaction associated with the lattice energy of LiCl. None of the above are endothermic.

Answer 1

we know that

if energy is required , it is endothermic

and

if energy is released , it is exothermic

A)

ionization energy of potassium

here

we require energy to ionize

so

it is endothermic

B)

heat of formation of CaS

in this case

the reaction is exothermic

C)

formation of F2

in this the energy required is zero

so

it is neither endothermic nor exothermic

D)

lattice enrgy og LiCl

in this case

it is exothermic