Question

For the following processes, say whether the overall energy change is positive or negative.

a) sublimation of a solid

b) break a chemical bond

c) ionize an atom

d) add an electron to a chlorine atom

e) condense isolated ions into a solid

Please explain the answers to each part, Thank You!

Answer 1

a) sublimation of a solid
Here solid changes to gas and it requires energy
so, overall energy change is positive

b) break a chemical bond
to break a bond, energy is required
so, overall energy change is positive

c) ionize an atom
to ionize an atom, energy is required
so, overall energy change is positive

d) add an electron to a chlorine atom
while adding electron, energy is released
so, overall energy change is negative

e) condense isolated ions into a solid
to convert ions to solid, electrons are added. energy is released
so, overall energy change is negative