The volume of the gas at 0'C and 700mm pressure is 760 CC.The no.of molecules present in this volume is ?

 

Asked by minipkda | 18th Aug, 2018, 08:46: PM

Expert Answer:

Given:
 
Temperature T = 0 °C
 
                      = 273 K
 
Pressure P = 700 mm
 
1 atm = 760 mmHg
 
Therefore, 
 
straight P equals 700 over 760 space atm
Volume V = 760 cc
 
              = 760×10-3 litre
 
We space have comma

PV space equals space nRT

straight n equals PV over RT

space space equals fraction numerator open parentheses begin display style bevelled 700 over 760 end style close parentheses cross times 760 cross times 10 to the power of negative 3 end exponent over denominator 0.0821 cross times 273 end fraction

straight n equals 0.031 space mole

1 space mole space equals space 6.022 cross times 10 to the power of 23 space molecules

0.031 space mole space equals space 6.022 cross times 10 to the power of 23 space cross times space 0.031

space space space space space space space space space space space space space space space space space space space equals 1.88 cross times 10 to the power of 22 space molecules
The 1.88×1022 molecules are present in the given volume of gas.

 
 

Answered by Varsha | 20th Aug, 2018, 12:08: PM