Phosphoric acid reacts with zinc to produce hydrogen gas and zinc phosphate. How many grams of acid are required to produce 5.3 liters of hydrogen at 743mmHg and 27.0 degrees Celsius

Answer 1

Use PV = nRT and convert the gas volume to STP and solve for n. Then follow this example problem to convert moles H2 to moles H3PO4 and to grams.
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