From the diagram,

55°C = 7 moles; 40°C = 6 moles.

Amount of solute deposited = 7 - 6 = 1 mole.

1000 cm3 = 1 mole

200 cm3 = x

x = 200×11000
= 0.20 mole.

<p><img alt="chemistry-4" class="wp-image-61346 alignnone" height="335" src="https://data.ulearngo.com/assets/63a7bf72-acaf-442b-a1a7-a38a9f52c330" width="501"/></p><p class="q_question">Read the vertical axis as moles of solute per \(1\,\mathrm{dm^3}\) of saturated solution. From the graph, estimate the amount of solute deposited when \(200\,\mathrm{cm^3}\) of solution, saturated at \(55^\circ\mathrm{C}\), is cooled to \(40^\circ\mathrm{C}\). Assume excess solute crystallizes and the solution volume stays unchanged. Choose the closest amount.</p>

Earlier discussion