Problem: Taking into account the vapor pressure of water, how many moles of hydrogen gas, n, are present in 319 mL at 752 torr and 29 °C? The value of the gas constant R is 0.08206 L ⋅ atm/(mol ⋅ K). You may also find the conversion factors 1 atm = 760 torr and TK = TC + 273 useful.Express the number of moles to three significant figures.A 0.250-g sample of a magnesium-aluminum alloy dissolves completely in an excess of HCl(aq). When the liberated H2(g) is collected over water at 29 °C and 752 torr, the volume is found to be 319 mL. The vapor pressure of water at 29 °C is 30.0 torr.

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Taking into account the vapor pressure of water, how many moles of hydrogen gas, n, are present in 319 mL at 752 torr and 29 °C? The value of the gas constant R is 0.08206 L ⋅ atm/(mol ⋅ K). You may also find the conversion factors 1 atm = 760 torr and TK = TC + 273 useful.

Express the number of moles to three significant figures.


A 0.250-g sample of a magnesium-aluminum alloy dissolves completely in an excess of HCl(aq). When the liberated H2(g) is collected over water at 29 °C and 752 torr, the volume is found to be 319 mL. The vapor pressure of water at 29 °C is 30.0 torr.

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