Question

Calculate the no. of atoms present in 11.5 litres of H2 at N.T.P.

Answer 1

We know that, at STP /NTP, 1 mole of any gas contains 22.4 L of it.So, 22.4 L of H2 = 1 mole. so11.5 L of H2 = (1/22.4 ) x 11.5 mole = 0.51 moles of H2 gas. As ,1 mole of H2 = 6.022 x 1023molecules of H2 = 2 x 6.022 x 1023atoms of H2  Hence, 0.51 mole of  =  2 x 6.022 x 1023 x 0.51 atoms of H2 = 6.14 x 1023 atoms of H2