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Started slowing down as magnesium disappeared. Some HCl went out the stopper. Some bubbles stuck to the side of the tube and to the string. Magnesium eventually disappeared.

Calculations:

1. 1. Number of moles of magnesium
      0.04/24.30 = 0.00165 moles of hydrogen reacted.
      
   2. Partial pressure of hydrogen
      29.00*2.54/10 = 736.6 mmHg
      736.6-19.25 = 717.35
      717.35/760 = 0.944 atm of hydrogen
   3. Volume at 1 atm
      P₁V₁=P₂V₂   0.944*44.85=1.00*V₂ V₂=42.3mL
   4. Volume at 273.15 ^oK
      V₁/T₁=V₂/T₂   42.3/(21.5+273.15)=V₂/273.15
      V₂=39.2mL
   5. Volume of 1 mol hydrogen at STP
      (29.2/1000)/0.00165=23.8 mol hydrogen

Conclusion:

The purpose of this lab was to calculate the molar volume of hydrogen. We achieved this by mixing a known amount of magnesium with HCl to form hydrogen gas in a eudiometer. We used he mass of the magnesium to find the moles of Mg and H₂, calculated the partial pressure of H₂, standardized it to STP, and converted that to density of H₂ at STP. It was calculated to be 23.8 mol.