Question

How many molecules are there in 9.4g of H2

Answer 1

Answer: You start with 9.4 x 1025 molecules of H2.

You know that an Avogadro's number of molecules of H2 has a mass of 2.0 g.

To solve, 9.4 x 1025 molecules H2 x (2.0 g H2 / 6.023 x 1023 molecules H2) = 312. g H2