Question

A certain amount of metal whose equivalent mass is 28 displaceso 0.7 Lit of H2 at STP from all acid hence mass of the elements is?

Answer 1

We know that 1 mole of H2 at STP occupies volume = 22.4 L

Given, 0.7 L H2 at STP = 0.7/22.4 = ~ 0.0313 moles.

The weight of element  = Moles of H2 * equivalent weight of metal * Mass of H2

                                        = 0.0313 x 28 x 2

                                        = 1.7528 grams.

Hope this helps!