A 0.418 g sample of gas has a volume of \(115 \mathrm{mL}\) at \(66.3^{\circ} \mathrm{C}\) and \(743 \mathrm{mm} \mathrm{Hg} .\) What is the molar mass of this gas?

Short Answer

Expert verified
The molar mass of the gas is approximately 103.58 g/mol.

Step by step solution

01

Convert the pressure from mmHg to atm

Knowing that \(1 \: atm \approx 760 \: mmHg \), the pressure is converted to atm by dividing 743 by 760, approximately equal to 0.977 atm.
02

Convert the volume from mL to L

Since 1 L contains 1000 mL, the volume is 115 mL, which is equivalent to 0.115 L.
03

Convert the temperature from Celsius to Kelvin

The Kelvin scale is used in gas law calculations. The temperature in Kelvin can be found by adding 273.15 to the Celsius temperature, resulting in a temperature of \(339.45 \: K\).
04

Use the Ideal Gas Law equation to solve for the number of moles, n

Next, rearrange the ideal gas law equation to solve for the number of moles \(n = P*V/(R*T)\). Substituting the previous values and using \(R = 0.0821 \: L*atm/(K*mol)\), the number of moles n is approximately 0.004036 mol.
05

Calculate molar mass given mass and number of moles

Finally, to find the molar mass, you divide the given mass of the sample by the number of moles calculated in step 4. Given mass is 0.418 g. Thus, molar mass is approximately 103.58 g/mol.

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Most popular questions from this chapter

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