Question

A gas occupies 16.3 l at stp. what volume will it occupy at 735 torr and 57°c?

Answer 1

Use the equation PV=nRT to find no. of moles (n)
For this;
At STP
Pressure= P= 1 atm
Temperature=T = 273.16 K
Volume= V= 16.3 L = 16.3 dm³
R = 0.0821 dm³ atm K⁻¹ mol⁻¹
Now,
PV= nRT
(1)(16.3)=n(0.0821)(273.16)
n = 0.727 mol

Now, again using the same equation for
Pressure=P= 735 torr
Temperature=T= 57°C
T= 57+273 =330 K
n= 0.727 mol (form previous calculation)
R= 62.4 dm³ torr K⁻¹ mol⁻¹
Now,
PV= nRT
(735)V= (0.727)(62.4)(330)
V= 20.37 dm³