Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Medical
  • 5 moles of liquid $X$ and 10 moles of liquid $Y$ make a solution having a vapour pressure of 70 torr. The vapour pressures of pure $X$ and $Y$ are 63 torr and 78 torr respectively. Which of the following is true regarding the described solution?

Q.90) 5 moles of liquid $X$ and 10 moles of liquid $Y$ make a solution having a vapour pressure of 70 torr. The vapour pressures of pure $X$ and $Y$ are 63 torr and 78 torr respectively. Which of the following is true regarding the described solution?

A) The solution has volume greater than the sum of individual volumes.

B) The solution shows positive deviation.

C) The solution shows negative deviation.

D) The solution is ideal.

 

Answers (1)

best_answer

Q.90) We are given:
- Mole of $\mathrm{X}=5$
- Mole of $\mathrm{Y}=10$
- Total moles $=15$

So:
- Mole fraction of $X, \chi_X=\frac{5}{15}=\frac{1}{3}$
- Mole fraction of $\mathrm{Y}, \chi_Y=\frac{10}{15}=\frac{2}{3}$

Pure vapor pressures:
- $P_X^0=63$ torr
- $P_Y^0=78$ torr

Observed vapor pressure of the solution $=70$ torr

Step 1: Calculate Expected Vapor Pressure (Ideal Solution)
Using Raoult's law for ideal solution:

$$
P_{\text {deal }}=\chi_X P_X^0+\chi_Y P_Y^0=\left(\frac{1}{3}\right)(63)+\left(\frac{2}{3}\right)(78)=21+52=73 \text { torr }
$$


Step 2: Compare with Given Vapor Pressure
- Expected (ideal): 73 torr
- Actual (given): 70 torr
- Actual < Ideal $\Rightarrow$ Negative deviation

Hence, the correct answer is option (3).

 

Posted by

AANIQA QAYOOM

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks

Similar Questions

Trending Articles/News

anam-khan

Want a career in medicine without NEET? Consider paramedical courses after Class 12
anam-khan

AFMC hikes MBBS seat leaving bond penalty, mandates 7 years of commission service
anam-khan

‘Patience and not backing down’: Kabir Paharia’s SC fight eases MBBS admissions for disabled candidates

Latest Question