Embibe Experts Solutions for Chapter: Some Basic Concepts of Chemistry, Exercise 3: EXERCISE-3

A mineral consists of an equimolar mixture of the carbonates of two bivalent metals. One metal is present to the extent of $13.2\%$ by weight. $2.58 \mathrm{g}$ of the mineral on heating lost $1.232 \mathrm{g}$ of ${\mathrm{CO}}_2.$ Calculate the $\%$ by weight of the other metal.

The density of mercury is $13.6 \mathrm{g}/{\mathrm{cm}}^3.$ Estimate the $\mathrm{b}$ value.

How many $\mathrm{mL}$ of $0.1 \mathrm{N} \mathrm{HCl}$ are required to react completely with $1 \mathrm{g}$ mixture of ${\mathrm{Na}}_2{\mathrm{CO}}_3$ and ${\mathrm{NaHCO}}_3$ containing equimolar amounts of two?

$1.5 \mathrm{g}$ of chalk were treated with $10 \mathrm{mL}$ of $4 \mathrm{N}-\mathrm{HCl}.$ The chalk was dissolved and the solution made to $100 \mathrm{mL}, 25 \mathrm{mL}$ of this solution required $18.75 \mathrm{mL}$ of $0.2 \mathrm{N}-\mathrm{NaOH}$ solution for complete neutralisation. Calculate the percentage of pure ${\mathrm{CaCO}}_3$ in the sample of chalk?

The neutralization of a solution of $1.2 \mathrm{g}$ of a substance containing a mixture of ${\mathrm{H}}_2{\mathrm{C}}_2{\mathrm{O}}_4·2{\mathrm{H}}_2\mathrm{O},{\mathrm{KHC}}_2{\mathrm{O}}_4·{\mathrm{H}}_2\mathrm{O}$ and different impurities of a neutral salt consumed$18.9 \mathrm{mL}$ of $0.5 \mathrm{NNaOH}$ solution. On titration with ${\mathrm{KMnO}}_4$ solution, $0.4 \mathrm{g},$ of the same substance needed $21.55 \mathrm{mL}$ of $0.25 {\mathrm{NKMnO}}_4.$ Calculate the $\%$ composition of ${\mathrm{H}}_2{\mathrm{C}}_2{\mathrm{O}}_4·2{\mathrm{H}}_2\mathrm{O}$ in the mixture.

A solution of a $0.4 \mathrm{g}$ sample of ${\mathrm{H}}_2{\mathrm{O}}_2$ reacted with $0.632 \mathrm{g}$ of ${\mathrm{KMnO}}_4$ in the presence of sulphuric acid. Calculate the percentage purity of the sample of ${\mathrm{H}}_2{\mathrm{O}}_2.$

Calculate the amount of lime $\mathrm{Ca}(\mathrm{OH}{)}_2$ required to remove the hardness in $60$ litre of pond water containing $1.62\mathrm{mg}$ of calcium bicarbonate per $100 \mathrm{mL}$ of water.

$10 \mathrm{g}$ sample of bleaching powder was dissolved into water to make the solution one litre. To this solution $35 \mathrm{mL}$ of $1.0\mathrm{M}$ Mohr salt solution was added containing enough ${\mathrm{H}}_2{\mathrm{SO}}_4.$ After the reaction was complete, the excess Mohr salt required $30 \mathrm{mL}$ of $0.1{\mathrm{MKMnO}}_4$ for oxidation. Find out the $\%$ of available ${\mathrm{Cl}}_2$ approximately is $(\mathrm{mol} \mathrm{wt}. 71).$