Question

How does the formation of a solution involve energy?

Solution

Verified
Step 1
1 of 2

During the formation of a solution energy is either released ($\textbf{exothermic reaction}$) or absorbed ($\textbf{endothermic reaction}$).

In order for a solution to be formed the attraction between solute particles and the attraction between solvent particles must be broken. Breaking these attractions requires energy.

When these attractions are broken, new attractions form between solute and solvent particles. The formation of these new attractions releases energy.

The difference between these energies will dictate whether the reaction will be exothermic or endothermic.

For example when sodium hydroxide ($NaOH$) is dissolved in water, the energy it releases when the new attractions between solvent and solute particles form is greater than the energy required to break the attractions between individual solvent and individual solute particles. This means that this reaction will be exothermic (the solution will become warmer).

When ammonium nitrate ($NH_{4}NO_{3}$) dissolves in water, the energy required to break the attractions between individual solvent and individual solute particles is greater than the energy it releases when the new attractions between solvent and solute particles form. This means that this reaction will be endothermic (the solution will become colder).

Recommended textbook solutions

Physical Science

1st EditionISBN: 9780076774562McGraw-Hill
1,174 solutions

Physical Science Concepts in Action

2nd EditionISBN: 9780131663053Frank, Wysession, Yancopoulos
1,490 solutions

Nelson Science Perspectives 9

1st EditionISBN: 9780176355197Doug Fraser, Jeff Major, Maurice DiGiuseppe
1,835 solutions

Nelson Science Perspectives 10

1st EditionISBN: 9780176355289Christy C. Hayhoe, Doug Hayhoe, Jeff Major, Maurice DiGiuseppe
1,359 solutions