NEET Practice Questions (MCQs) with Answers & Solutions

(d)

In this process water gas (CO + H2, prepared from coal and water at 1270 K) is mixed with two times its volume of steam passed over catalyst Fe₂O₃, in the presence of promoter Cr₂O₃ or ThO₂ at 773 K giving products CO₂ and H₂.

CO₂ is dissolved in water under pressure (20 to 25 atm) and is removed leaving behind un dissolved H2.

(d) ${\mathrm{H}}_2{\mathrm{O}}_2 \stackrel{ }{\rightleftharpoons }{\mathrm{H}}^{+} + {\mathrm{HO}}_2^{-}$

(a)

 $$\begin{gathered} 2{\mathrm{I}}^{-} \stackrel{ }{\to } {\mathrm{I}}_2^0 + 2e \\ 2e + {\mathrm{O}}_2^{1-} \stackrel{ }{\to }2{\mathrm{O}}^{2-} \end{gathered}$$

(d) These all are characteristics of perhydrol.

(b) Ortho and para-hydrogen possess same electronic arrangement but different spin of nuclei.

 Ortho and para hydrogen are similar in chemical properties but differ in some of the physical properties.

(i) Melting point of para hydrogen is 13.83K while that of ordinary hydrogen is 13.95 K.

(ii) Boiling point of para hydrogen 20.26K while that of ordinary hydrogen is 20.39K.

(iii) The vapour pressure of liquid para hydrogen is higher than that of ordinary liquid hydrogen.

            The magnetic moment of para hydrogen is zero since the spins neutralise each other while in the case of ortho , it is twice than that of a proton.

Para hydrogen possesses a lower internal molecular energy than ortho form.

(c) ${\mathrm{BaO}}_2 + {\mathrm{CO}}_2 + {\mathrm{H}}_2\mathrm{O} \stackrel{ }{\to } {\mathrm{BaCO}}_3 + {\mathrm{H}}_2{\mathrm{O}}_2$

(d) Bicarbonates of Ca and Mg are responsible for temporary hardness.

(b) ${\mathrm{BaO}}_2 + {\mathrm{CO}}_2 + {\mathrm{H}}_2\mathrm{O} \stackrel{ }{\to }{\mathrm{H}}_2{\mathrm{O}}_2 + {\mathrm{BaCO}}_3$

(d) $$\begin{gathered} 5e + {\mathrm{Mn}}^{7+}\stackrel{ }{\to } {\mathrm{Mn}}^{2+} \\ {\mathrm{O}}_2^{1-}\stackrel{ }{\to }{\mathrm{O}}_2^0 +2e \end{gathered}$$