calculate the number of atoms present in 3.4g of h2s?

Answer 1

Convert 3.4 g H2S (h2s means nothing to me) to moles. mols = grams/molar mass.

Then convert mole H2S to molecules remembering that there are 6.022 x 10^23 molecules H2S in a mole of H2S.
Finally, multiply that number by 3 since there are three atoms per molecule of H2S (2 atoms H and 1 atom S).

Answer 2

0.1 mole

Answer 3

1 mile = 6.22×1^23

Answer 4

1 mole=6.022×10^23

Answer 5

1 mole of h2s contains 6.022×10^23 atoms
0.1 mole of h2s contains 0.1× 6.022×10^23 atoms
= 6.022×10^22 atoms