+91-8076753736[email protected]
logo
logo
-->

Electrochemistry

Question
CBSEENCH12010376
Wired Faculty App

Calculate e.m.f of the following cell at 298 K:

2 Cr space left parenthesis straight s right parenthesis space plus 3 Fe to the power of 2 plus end exponent space left parenthesis 0.1 space straight M right parenthesis space rightwards arrow space 2 Cr to the power of 3 plus end exponent space left parenthesis 0.01 space straight M right parenthesis space plus 3 Fe left parenthesis straight s right parenthesis space Given colon space straight E to the power of 0 space left parenthesis Cr to the power of 3 plus end exponent vertical line Cr right parenthesis space equals space minus 0.70 space straight V space space space space space space space space space space space straight E to the power of 0 space left parenthesis Fe to the power of 2 plus end exponent vertical line Fe right parenthesis space equals negative 0.44 space straight V

Solution
2 Cr space left parenthesis straight s right parenthesis space space plus 3 Fe to the power of 2 plus end exponent space left parenthesis 0.1 straight M right parenthesis space rightwards arrow space 2 Cr cubed left parenthesis 0.01 straight M right parenthesis space plus 3 Fe left parenthesis straight s right parenthesis Given colon space straight E subscript Cr to the power of 3 plus end exponent divided by Cr end subscript superscript 0 space equals negative 0.74 straight V straight E subscript Fe to the power of 2 plus end exponent divided by Fe end subscript superscript 0 space equals space minus 0.44 straight V The space cell space can space be space represented space as space follows colon Cr vertical line space Cr to the power of 3 plus end exponent space left parenthesis 0.01 straight M right parenthesis space vertical line vertical line space Fe to the power of 2 plus end exponent left parenthesis 0.1 straight M right parenthesis vertical line space Fe left parenthesis straight s right parenthesis straight E subscript cel superscript 0 space equals space straight E subscript Fe to the power of 2 plus end exponent divided by Fe end subscript superscript 0 space minus straight E subscript Cr to the power of 3 plus end exponent divided by Cr end subscript superscript 0 straight E subscript cell superscript 0 space equals negative 0.44 minus left parenthesis negative 0.74 right parenthesis space equals space 0.30 space straight V straight E subscript cell space equals space straight E subscript cell superscript 0 space minus fraction numerator 2.303 space RT over denominator nF end fraction space log space fraction numerator left square bracket Cr to the power of 3 plus end exponent right square bracket squared over denominator left square bracket Fe to the power of 2 plus end exponent right square bracket cubed end fraction straight E subscript cell space equals space 0.30 space minus fraction numerator 0.0591 over denominator 6 space end fraction log space fraction numerator left parenthesis 0.01 right parenthesis squared over denominator left parenthesis 0.1 right parenthesis cubed end fraction straight E subscript cell space equals space 0.30 space plus 0.01 straight E subscript cell space equals space 0.31 space straight V

Some More Questions From Electrochemistry Chapter

Why does the conductivity of a solution decrease with dilution?

Suggest a way to determine the Λ°m value of water.

The molar conductivity of 0.025 mol L–1 methanoic acid is 46.1 S cm2 mol–1. Calculate its degree of dissociation and dissociation constant. Give λ°(H+) = 349.6 S cm2 mol–1 and λ° (HCOO– ) = 54.6 s cm2 mol–1.

If the current of 0.5 ampere flows through a metallic wire for 2 hours, then how many electrons flow through the wire?

Suggest a list of metals that are extracted electrolytically.

Consider the reaction: Cr2O72– + 14H+ + 6e- → 2Cr3+ + 8H2O
What is the quantity of electricity in coulombs needed to reduce 1 mol of Cr2O72-?

Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.

Suggest two materials other than hydrogen that can be used as fuels in fuel cells.

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation