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Pressure of 1 g of an ideal gas A at 27 | Class 11 Chemistry Chapter States of Matter, States of Matter NCERT Solutions

Q5.

Pressure of 1 g of an ideal gas A at 27 °C is found to be 2 bar. When 2 g of another ideal gas B is introduced in the same flask at same temperature the pressure becomes 3 bar. Find a relationship between their molecular masses.

Mass of gas A , WA = 1g

Mass of gas B,  WB = 2g

Pressure exerted by the gas A = 2 bar

Total pressure due to both the gases = 3 bar

In this case temperature & volume remain constant

Now if MA & MB are molar masses of the gases A & B respectively,therefore

pA V= WA RT/MA & Ptotal V = (WA/MA + WB/ MB) RT

= 2 X V = 1 X RT/MA & 3 X V = (1/MA + 2/MB)RT

From these two equations, we get

3/2 = (1/MA + 2/MB) / (1 /MA) = (MB + 2MA) / MB

This result in 2MA/ MB = (3/2) -1 = ½

OR MB = 4MA

Thus, a relationship between the molecular masses of A and B is given by

4MA = MB   

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What is the correct answer to: Pressure of 1 g of an ideal gas A at 27 °C is found to be 2 bar. When 2 g of another ideal gas B is introduced in the same flask at same temperature the pressure becomes 3 bar. Find a relationship between their molecular masses.?

Mass of gas A , WA = 1g

Mass of gas B,  WB = 2g

Pressure exerted by the gas A = 2 bar

Total pressure due to both the gases = 3 bar

In this case temperature & volume remain constant

Now if MA &...

How do you solve Pressure of 1 g of an ideal gas A at 27 °C is found to be 2 bar. When 2 g of another ideal gas B is introduced in the same flask at same temperature the pressure becomes 3 bar. Find a relationship between their molecular masses. step by step?

Step-by-step explanation:
• Mass of gas A , WA = 1g
•
• Mass of gas B,  WB = 2g
•
• Pressure exerted by the gas A = 2 bar

What common mistakes should be avoided in this question?

Students often lose marks by skipping steps, writing incomplete explanations, or misunderstanding keywords used in the question.

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Student Discussion

Sana
Class · · , · Oct 17, 2019
Why it can't be just p directly proportional to molecular weight by which mw1=2mw2
👍 👎 Reply
Rockstar
Class · · , · Sep 20, 2019
Greatest explanation
👍 👎 Reply
Samadrita
Class · · , · Jun 27, 2019
Thank you.
Really helpful 😀
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Lakshita joshi
Class · · , · Feb 27, 2019
R is here universal gas constant
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Lakshita joshi
Class · · , · Feb 27, 2019
R is here universal gas constant
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Niti
Class · · , · Nov 08, 2018
Why does the volume is constant here ... it is not given in question ..????
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shiva tiwari allhabadi
Class · · , · Oct 30, 2018
W means n
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shiva tiwari allhabadi
Class · · , · Oct 30, 2018
R means 0.281 atm
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shiva tiwari allhabadi
Class · · , · Oct 30, 2018
Anita are u know the formula of mAss\molarmass =n and here n is represented by W
😕😕
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Anita
Class · · , · Aug 13, 2018
What is meaning of wA/mA+wB/mB in this question please answer
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