Embibe Experts Solutions for Chapter: Some Basic Concepts of Chemistry, Exercise 1: AIPMT - 25th July 2015

What mass of $95\%$ pure ${\mathrm{CaCO}}_3$ will be required to neutralise $50 \mathrm{mL}$ of $0.5 \mathrm{M} \mathrm{HCl}$ solution according to the following reaction?

${\mathrm{CaCO}}_{3\left(\mathrm{s}\right)}+2{\mathrm{HCl}}_{\left(\mathrm{aq}\right)}\to {\mathrm{CaCl}}_{2\left(\mathrm{aq}\right)}+{\mathrm{CO}}_{2\left(\mathrm{g}\right)}+2{\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{l}\right)}$

[Calculate upto second place of decimal point]

In one molal solution that contains $0.5$ mole of a solute, there is

An organic compound contains $80\%$ (by wt.) carbon and remaining percentage of hydrogen. The right option for the empirical formula of this compound is: [Atomic wt. of $\mathrm{C}$ is $12$ and of $\mathrm{H}$ is $1$]

One mole of carbon atom weighs $12\mathrm{g}$, the number of atoms in it is equal to, (Mass of carbon $-12$ is $\left.1.9926\times {10}^{-23}\mathrm{g}\right)$

Which one of the followings has maximum number of atoms?

The number of moles of hydrogen molecules required to produce $20$ moles of ammonia through Haber’s process is:

When $22.4$ litres of ${\mathrm{H}}_2\left(\mathrm{g}\right)$ is mixed with $11.2$ litres of $\mathrm{C}{\mathrm{l}}_2\left(\mathrm{g}\right),$ each at STP, the moles of $\mathrm{H}\mathrm{C}\mathrm{l}\left(\mathrm{g}\right)$ formed is equal to

$1.0\mathrm{ }\mathrm{g}$ of magnesium is burnt with $0.56\mathrm{ }\mathrm{g}$ ${\mathrm{O}}_2$ in a closed vessel. Which reaction is left in excess and how much? (At, wt. $\mathrm{M}\mathrm{g}=24; \mathrm{O}=16)$