Chemistry Past Questions and Answers

Hydrated salt of formula \(\mathrm{MSO}_{4} \cdot \mathrm{XH}_{2} \mathrm{O}\) contains \(45.3 \%\) by mass of water of crystallization. Calculate the value of \(X\).<br/><br/>\([M=56, S=32, O=16, H=1]\)

A given quantity of a gas occupies a volume of \(228 \mathrm{~cm}^{3}\) at a pressure of \(750 \mathrm{mmHg}\). What will be its volume at atmospheric pressure?

A certain volume of a gas at \(298 \mathrm{~K}\) is heated such that its volume and pressure are now four times the original values. What is the new temperature?

The mass of silver deposited when a current of \(10 \mathrm{~A}\) is passed through a solution of silver salt for 4830s?<br/><br/>\(\left[\mathrm{Ag}=106 \mathrm{~g}, \mathrm{~F}=96500 \mathrm{Cmol}^{-1} \rsight]\)

\(2 \mathrm{CO}+\mathrm{O}_{2} \rightarrow 2 \mathrm{CO}_{2(\mathrm{~g})}\). Given that \(\Delta \mathrm{H}[\mathrm{CO}]\) is \(-110.4 \mathrm{kJmol}\) and \(\mathrm{H}\left[\mathrm{CO}_{2} \right]\) is \(-393.0 \mathrm{kJmol}^{-1}\) the energy change of the reaction above is?