Question

1. An evaluation of R was performed using the procedures outlined in this exercise. The barometric pressure was 735 torr and the temperature was 21.5 degree Celsius. The volume of H₂(g) was collected was 32.7 mL. The calculated value of R was 0.0817 L*atm/mol*K.

a) How many grams of Mg metal were used in this determination?

b) If the correction for the vapor pressure of water had not been performed, what would be the calculated value of R?

c) If the syringe volume had been incorrectly read resulting in a calculated H₂ volume of 30.6 mL, what would be the percent error in the calculated value of R?

Answer 1

Ams: Given The baro mefric = 735 torr ressure 215C The 2 was olede d wlag 32.4 mL The volome of 0.0817 am noolk Evaluaton .o fapesimen! makes of mg a) Alhere PE Prespure 735-19-2) torr 760 715.8 760 0.9418 P VE 0.0327L R Gas Coms ton! 10.0820 7= Temperadure (215279 29y.5k

So, 0941x0-0327 modes o082/x2945 0-030 77 24 /7845 3 x 10-3 mel Mass 0.0 3159 0.0316 ..Ma ot Ma= 00316 the orrcton of water vapour prespure i nof done, -the final Prepgore the octal valve. would aleo be greak than Sa the 'R' alalate the adval value R andp are

PvnRT Wher Vvolume R- Gos Cams fand 7=Temperature Glven volome = 30.6 ml hemedly ved to a the lume H2as lower volime The value of R hs aluated wevki be B=30.6 x 0 0817 32.7 K0076 Latm/kmal l0.087- 0-014y)x 180 D0817 0.0 648X 100 6.y8 % 6.5 % peread 6.5 error=