Salts of metals ${X}, {Y}$ and ${Z}$ are electrolysed under identical condition using same quantity of electricity. It was observed that $4.2 {~g}$ of ${X}, 5.4 {~g}$ of ${Y}$ and $19.2 {~g}$ of ${Z}$ were deposited at respective cathode. If the atomic weights of ${X}, {Y}, {Z}$ are 7 , 27 and 64 respectively, then their ratio of valencies is

JEE CHEMISTRY MCQ: ELECTRO CHEMISTRY

1 Hard

1 of 1

Application +4 | -1

Salts of metals

{X}, {Y}

and

{Z}

are electrolysed under identical condition using same quantity of electricity. It was observed that

4.2 {~g}

{X}, 5.4 {~g}

{Y}

and

19.2 {~g}

{Z}

were deposited at respective cathode. If the atomic weights of

{X}, {Y}, {Z}

are 7 , 27 and 64 respectively, then their ratio of valencies is

View answer and explanation

Correct option: B

1: 3: 2

Option B (

1: 3: 2

) is correct because it represents the ratio of valencies calculated using Faraday's laws of electrolysis.

Practice All Chapter MCQs →

25^{\circ} \mathrm{C}

0.295 \mathrm{~V}

{p_1}{\kern 1pt} {\kern 1pt} \mathrm{and}{\kern 1pt} {\kern 1pt} {p_2}

\mathop {\mathrm{Pt}\left( {{\mathrm{H}_2}} \right)}\limits_{{p_1}} \left| {\mathop {{\mathrm{H}^ + }\left( {aq} \right)}\limits_{1\mathrm{ }M} } \right|\mathop {Pt\left( {{\mathrm{H}_2}} \right)}\limits_{{p_2}}

\mathrm{CuS}{\mathrm{O}_4}

{AlCl}_3

STP

({F}=96500 {C})

2 \mathrm{Ag}(\mathrm{s})+\mathrm{S}^{2-}(\mathrm{aq}) \rightarrow \mathrm{Ag}_2 \mathrm{S}(\mathrm{s})+2 \mathrm{e}^{-}

\mathrm{pH}=3

0.1 \mathrm{~M}-\mathrm{H}_2 \mathrm{S},

\mathrm{H}_2 \mathrm{S}, K_{\mathrm{a}_1}=10^{-8} ; K_{\mathrm{a}_2}=10^{-13}, K_{\mathrm{sp}}

\mathrm{Ag}_2 \mathrm{S}=4 \times 10^{-48},

E^{\circ}_{{\mathrm{Ag} | \mathrm{Ag}}^{+}}=0.80 \mathrm{~V},

\log 2=0.3,

2.303 R T / F=0.06