Question

find the mass of h2 produced Binary compounds of alkali metals and hydrogen react with water to produce H2(g). The H2H2 from the reaction of a sample of NaH with an excess of water fills a volume of 0.505 L above the water. The temperature of the gas is 35 ∘C∘C and the total pressure is 755 mmHg

Answer 1

Answer: Mass of hydrogen produced is 0.0376 g.

Explanation:

The reaction equation will be as follows.

$NaH(aq) + H_{2}O(l) \rightarrow H_{2}(g) + NaOH(aq)$

Now, formula for total pressure will be as follows.

  $P_{total} = P_{H_{2}} + P_{H_{2}O}$

Hence,    $P_{H_{2}} = P_{total} - P_{H_{2}O}$

                            = 755 mm Hg - 42.23 mm Hg

                            = 712.77 mm Hg

$P_{H_{2}} = \frac{712.77 \times 1 atm}{760 mm Hg}$

             = 0.937 atm

Now, we will calculate the moles of $H_{2}$ as follows.

   $P_{H_{2}}V = nRT$

   $0.937 atm \times 0.505 L = n \times 0.0821 \times 308.15 K$

      n = $\frac{0.473}{25.29}$ mol

         = 0.0187 mol

Therefore, mass of $H_{2}$ will be calculated as follows.

        $m_{H_{2}} = \frac{0.0187 mol \times 2.0158 g}{1 mol}$

                   = 0.0376 g

Thus, we can conclude that mass of hydrogen produced is 0.0376 g.