Question

What volume of hydrogen gas, at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) from the reduction of boron trichloride by hydrogen?

पर्याय

• 67.2 L

• 44.8 L

• 22.4 L

• 89.6 L

Answer 1

67.2 L

Explanation:

\[\ce{2BCl3 + 3H2 -> 2B + 6HCl}\]

or \[\ce{BCl3 + 3/2H2 -> B + 3HCl}\]

Now, since 10.8 g of boron requires hydrogen

= `3/2 xx 22.4` L at S.T.P.

Hence, 21.6 g of boron requires hydrogen

= `3/2 xx 22.4/10.8 xx 21.6`

= 67.2 L at S.T.P.