The
ideal gas equation
or 
(1)
or (1)
Find the formula weight of an unknown gas, if 0.98 grams of it occupies a volume of 440ml at 23oC and 749mmHg pressure.
Clues
Solution
Step
1- Find the pressure the gas exerts in kPa.
Step
2- Convert the temperature
from Celsius to Kelvin.
Step
3- Convert the volume from
millilitres to litres.
Step
4- Solve for the molar mass
Click on each step
for extra assistance
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The pressure of the gas is 749mmHg.
We must convert the pressure from mmHg to kilopascals.
760mmHg = 101.3kPa
So
(740/760) X 101.3 = 98.63kPa
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23 degrees Celsius is (273 + 23) = 296o K
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The volume needs to be converted
to litres.
To convert millilitres into litres we divide by 1000
440ml = 0.44litres
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Place the values of each variable in the formula and solve for the formula weight.
M = (0.98 X 8.31 X 296) / (98.63 X 0.44) = 55.55 atomic mass units
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|
The
ideal gas equation
or (1) |
|
Find the formula weight of an unknown gas, if 0.98 grams of it occupies a volume of 440ml at 23oC and 749mmHg pressure.
|
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