1. what is the mass of 22.4 l of h2 at stp? a.) 1.01 grams b.) 2.02 grams c.) 11.2 grams d.) 22.4 grams 2. read the chemical equation. mg + hcl → mgcl2 + h2 how many liters of hydrogen gas is produced at 298 k and 0.960 atm if 3.00 moles of hydrochloric acid react with an excess of magnesium metal? a.) 38.2 liters b.) 42.6 liters c.) 66.7 liters d.) 76.4 liters

Explanation:

1.    According to Avogadro's law 1 mole of every gas occupies 22.4 L. Therefore, it is given that volume is 22.4 L so, this means that number of moles equal to one.

Molar mass of hydrogen gas is 2.02 g/mol.

Hence, calculate the mass as follows.

    No. of moles =

or,        mass =

                     =

                     = 2 g

Therefore, mass of 22.4 L of at STP is 2.02 grams.

2.   The given data is as follows.

         P = 0.960 atm,                T = 298 K

         n = 3.00 moles,               V = ?

         R = 0.0821 atm L/K mol

So, calculate the volume using ideal gas equation as follows.

                   PV = nRT

                     V =

                         =

                         = 76.455 L

Thus, we can conclude that volume of the hydrogen gas produced is 76.455 L.

the answer is d. 74.02