NEET UG 2015 — Chemistry Physical Chemistry

2015mcqeasy

Which one is not equal to zero for an ideal solution?

Official previous-year question

Held on 30 Apr 2015 · Verified 9 Jul 2026.

Options

A
$\Delta {H}_{mixture}$
B
$\Delta {S}_{mixture}$
C
$\Delta {V}_{mixture}$
D
$\Delta P={P}_{Observed}-{P}_{Raoult}$

Did you get this right?

Solution

For the ideal solution

$\Delta {\text{H}}_{ \text{mixture}} =0,$ because new bond formed and break so no enthalpy gain or lose.

$\Delta {\text{S}}_{ \text{mixture}} >0,$ because randomness increasing on mixing on a solution.

$\Delta {\text{V}}_{ \text{mixture}} =0,$ ${e}^{-}$ because no new bond for or break so, no force of attraction change.

$\Delta \text{P}={\text{P}}_{ \text{observed}} -\Delta {\text{P}}_{ \text{Raoult}} =0;$ vapour pressure remains the same because of no force of attraction increase or decrease.

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NEET UG 2015 — Chemistry Physical Chemistry

2015mcqeasy

Which one is not equal to zero for an ideal solution?

Official previous-year question

Held on 30 Apr 2015 · Verified 9 Jul 2026.

Options

A
$\Delta {H}_{mixture}$
B
$\Delta {S}_{mixture}$
C
$\Delta {V}_{mixture}$
D
$\Delta P={P}_{Observed}-{P}_{Raoult}$

Did you get this right?

Solution

For the ideal solution

$\Delta {\text{H}}_{ \text{mixture}} =0,$ because new bond formed and break so no enthalpy gain or lose.

$\Delta {\text{S}}_{ \text{mixture}} >0,$ because randomness increasing on mixing on a solution.

$\Delta {\text{V}}_{ \text{mixture}} =0,$ ${e}^{-}$ because no new bond for or break so, no force of attraction change.

$\Delta \text{P}={\text{P}}_{ \text{observed}} -\Delta {\text{P}}_{ \text{Raoult}} =0;$ vapour pressure remains the same because of no force of attraction increase or decrease.

NEET UG 2015 — Chemistry Physical Chemistry

Options

Did you get this right?

Solution

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NEET UG 2015 — 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