How to Calculate Solubility from Solubility Product

In this JC2 webinar we want to learn how to calculate solubility from solubility product.

Let's take a look at this exercise.

calculate solubility AgBr

When an amount of salt that corresponds to its solubility (x) dissolves, a saturated solution is formed.

A saturated solution is at equilibrium since the concentration of its ions are maximum and constant.

Therefore it is relevant to use solubility product (Ksp), the equilibrium constant for the dissociation of sparingly soluble salts.

This means that solubility and solubility product are related to each other.

Check out the following video for an in-depth discussion of the relationship between solubility and solubility product.

Let's turn our focus back on the dissociation of AgBr.

calculate solubility AgBr dissociation

From the mole ratio we can deduce that x moldm-3 of AgBr (which corresponds to its solubility) will give x moldm-3 of Ag+ and x moldm-3 of Br-.

Therefore we can write down the Ksp and work out its relationship with solubility x.

calculate solubility determine Ksp in terms of solubility

We can then express solubility in terms of Ksp and calculate its value.

calculate solubility calculate solubility of AgBr

Let's look at another example Ag2CO3.

calculate solubility Ag2CO3

The method is essentially the same as the previous example.

We can write down its dissociation and figure out the concentration of Ag+ and CO32- in terms of solubility x.

calculate solubility Ag2CO3 dissociation

We can then have a relationship between Ksp and x, and solve for x given Ksp.

calculate solubility calculate solubility of Ag2CO3

Topic: Solubility Product, Physical Chemistry, A Level Chemistry, Singapore

Back to other previous Physical Chemistry Video Lessons.

Found this A Level Chemistry video useful?

Please LIKE this video and SHARE it with your friends!

Join my 17,000 subscribers on my YouTube Channel for new A Level Chemistry video lessons every week.

Check out other A Level Chemistry Video Lessons here!

Need an experienced tutor to make Chemistry simpler for you?

Do consider signing up for my JC Chemistry Tuition classes at Bishan or on-demand video lessons!