Chemistry Class-11: Chapter –1. Some Basic Concepts of Chemistry – Part-5

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The density of 3 molar solution of is 1.110 g mL–1. Calculate the molarity of the solution


molal solution of means that of are dissolved in of solvent.

∴ Mass of

(Since density of solution = 1.110g mL–1)

Since solution contains of


Volume of a solution changes with change in temperature, then, will the molality of the solution be affected by temperature? Give reason for your answer.


No, Molality of solution does not change with temperature since mass remains unaffected with temperature.


If of dissolves in of , calculate the mole fraction of each component in the solution. Also, determine the molarity of solution (specific gravity of solution is .


Number of moles of

Mass of solution

Volume of solution


The reactant which is entirely consumed in reaction is known as limiting reagent. In the reaction, when moles of A react with moles of B, then

(i) Which is the limiting reagent?

(ii) Calculate the amount of C formed?


According to the above equation, mols of ‘A’ require mols of ‘B’ for the reaction.

Hence, for

But we have only of ‘B’, hence, ‘B’ is the limiting reagent. So amount of ‘C’ formed is determined by amount of ‘B’.

Since of ‘B’ give mols of ‘C’. Hence 6 mols of ‘B’ will give