NEET UG 2021 — Chemistry Physical Chemistry

2021mcqhard

The molar conductance of $\mathrm{NaCl},\mathrm{HCl}$ and ${\mathrm{CH}}_{3}\mathrm{COONa}$ at infinite dilution are $126.45,426.16$ and $91.0{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$ respectively. The molar conductance of ${\mathrm{CH}}_{3}\mathrm{COOH}$ at infinite dilution is. Choose the right option for your answer.

Official previous-year question

Held on 30 Apr 2021 · Verified 9 Jul 2026.

Options

A
$201.28{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$
B
$390.71S{\mathrm{cm}}^{2}{\mathrm{mol}}^{-1}$
C
$698.28{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$
D
$540.48{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$

Did you get this right?

Solution

${\Lambda }_{m}^{\infty }({\mathrm{CH}}_{3}\mathrm{COOH})={\Lambda }_{m}^{\infty }({\mathrm{CH}}_{3}\mathrm{COONa})+{\Lambda }_{m}^{\infty }(\mathrm{HCl})-{\Lambda }_{m}^{\infty }(\mathrm{NaCl})$

$=91+426.16-126.45$

$=390.71S{\mathrm{cm}}^{2}{\mathrm{mol}}^{-1}$

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NEET UG 2021 — Chemistry Physical Chemistry

2021mcqhard

Official previous-year question

Held on 30 Apr 2021 · Verified 9 Jul 2026.

Options

A
$201.28{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$
B
$390.71S{\mathrm{cm}}^{2}{\mathrm{mol}}^{-1}$
C
$698.28{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$
D
$540.48{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}$

Did you get this right?

Solution

${\Lambda }_{m}^{\infty }({\mathrm{CH}}_{3}\mathrm{COOH})={\Lambda }_{m}^{\infty }({\mathrm{CH}}_{3}\mathrm{COONa})+{\Lambda }_{m}^{\infty }(\mathrm{HCl})-{\Lambda }_{m}^{\infty }(\mathrm{NaCl})$

$=91+426.16-126.45$

$=390.71S{\mathrm{cm}}^{2}{\mathrm{mol}}^{-1}$

Your note

NEET UG Physical Chemistry in other years

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Work through every NEET UG Physical Chemistry PYQ, year by year.

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NEET UG 2021 — Chemistry Physical Chemistry

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Solution

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NEET UG Physical Chemistry in other years

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NEET UG 2021 — Chemistry Physical Chemistry

Options

Did you get this right?

Solution

Your note

NEET UG Physical Chemistry in other years

More NEET UG Physical Chemistry questions

Other Chemistry topics for NEET UG

Organic Chemistry

Inorganic Chemistry

Keep practicing Physical Chemistry