# Calculating the Molar Volume of a Gas Experiment.

by harshalpatil (student)

## Calculations

Moles of magnesium

1 meter of magnesium = 1.78 g ±0.01

2 cm of magnesium = 1.78*2/100 = 0.0356 g ±0.01

Moles of Mg = Mass / Molar Mass

Moles of Mg = 0.0356/24.31 = 0.00146

% uncertainty in moles = 0.01+0 = 0.01%

% uncertainty to absolute uncertainty for moles = 0.01*0.00146/100 = 0.0000000464

Absolute uncertainty of moles = 0.00146000 mol ± 0.00000146

### Trial 1

Partial Pressure of Hydrogen

Partial Pressure of Hydrogen = Atmospheric Pressure – Vapor Pressure of water

Partial Pressure of Hydrogen = 102.2 – 2.2

Partial Pressure of Hydrogen = 100.0 kPa

% uncertainty for Atmospheric Pressure = 0.05/102.2*100 = 0. 489%

% uncertainty for Vapor Pressure = 0%

% uncertainty for Partial Pressure = 0. 489%

% uncertainty to absolute uncertainty = 0. 489*100.0/100 = ±0. 489

Absolute uncertainty of Partial Pressure = 100.000 kPa ±0. 489

Volume occupied by one mole of hydrogen at STP

P1V1/T1 = P2V2/T2

100*0.037/292 = 100*V/273

V = 0.0346 dm3

% uncertainty for Pressure 1 = 0. 489%

% uncertainty for Volume 1 = 0.0005/0.037*100 = 1.35%

% uncertainty for Temperature 1 = 0.5/292*100 = 0.171%

% uncertainty for Pressure 2 = 0%

% uncertainty for Temperature 2 = 0%

% uncertainty for Volume ...