The number of moles of solute present in one litre of solution is called molarity. It is the most common way of expressing the concentration of a solution in the laboratory. It changes with temperature because the volume of a solution alters due to expansion and contraction of the liquid with temperature. The formula to calculate molarity is: Molarity = Number of moles of solute Volume of solution in Litre = n v

Molality is the number of moles of solute present in one kilogram of a solvent. It is represented by m . It does not change with temperature because the mass of the solvent does not change so due to this reason it is a better way of determining the concentrations of solutions. m = Number of moles of solute Mass of the solvent in kg

Formality of a solution may be defined as the number of gram formula masses of the ionic solute dissolved per litre of the solution. Commonly, the term formality is used to express the concentration of the ionic solids which do not exist as molecules but exist as a network of ions. As formality depends on the volume of solution, the formality of a solution changes with change in temperature. Formality ( F ) = Number of gram masses of solute Volume of solution in litres The unit of formality is moles/litre.

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ICSE Chemistry>Chapter 2 - Solutions>SHORT ANSWER TYPE QUESTIONS

Dr. H.C. Srivastava and SUMEDHA SRIVASTAVA Solutions for Chapter: Solutions, Exercise 3: SHORT ANSWER TYPE QUESTIONS

Author:Dr. H.C. Srivastava & SUMEDHA SRIVASTAVA

Dr. H.C. Srivastava Chemistry Solutions for Exercise - Dr. H.C. Srivastava and SUMEDHA SRIVASTAVA Solutions for Chapter: Solutions, Exercise 3: SHORT ANSWER TYPE QUESTIONS

Attempt the free practice questions on Chapter 2: Solutions, Exercise 3: SHORT ANSWER TYPE QUESTIONS with hints and solutions to strengthen your understanding. ICSE Chemistry solutions are prepared by Experienced Embibe Experts.