# chemistry

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Hydrogen gas can produced by the reaction between metallic aluminum and aqueous hydrochloric acid

2Al+6HCl----2AlCl3+3H2

Hydrogen gas produced by this reaction is typically collected via water displacement, during which time the hydrogen gas becomes saturated with water vapor. If 271.6 mL of gas with a total pressure 1.03 atm was collected via water displacement at 29.4 °C, what is the partial pressure of hydrogen gas in the sample? How many grams of aluminum must have reacted to produce this quantity of hydrogen gas? The vapor pressure of water at 29.4 °C is 30.75 torr.

• chemistry -

use the given info to find water vapor pressure of water at 29.4C, then subtract that from 1.03 atm.

• chemistry -

sorry but i just got soo confused

• chemistry -

Ptotal = pH2(gas) + pH2O(gas)
You know Ptotal and pH2O, what is pH2.
Then PV = nRT tells you n for mols H2. From there you have a stoichiometry problem to go from mols H2 to mols Al to g Al.

• chemistry -

Hydrogen gas produced by this reaction is typically collected via water displacement, during which time the hydrogen gas becomes saturated with water vapor. If 220.3 mL of gas with a total pressure 1.17 atm was collected via water displacement at 29.4 °C, what is the partial pressure of hydrogen gas in the sample?

How many grams of aluminum must have reacted to produce this quantity of hydrogen gas? The vapor pressure of water at 29.4 °C is 30.75 torr.