Answer:
9.89 x 10²³ molecules H₂S
Explanation:
To find the molecules of H₂S, you need to (1) convert grams S to moles S (via the atomic mass of sulfur), then (2) convert moles S to moles H₂S (via the mole-to-mole ratio from equation coefficients), and then (3) convert moles H₂S to molecules H₂S (via Avogadro's Number). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the sig figs of the given value.
Atomic Mass (S): 32.065 g/mol
2 H₂S(s) + SO₂(g) -----> 3 S(s) + 2 H₂O(l)
Avogadro's Number:
6.022 x 10²³ molecules = 1 mole
79.0 g S 1 mole 2 moles H₂S 6.022 x 10²³ molecules
--------------- x --------------- x ---------------------- x ------------------------------------- =
32.065 g 3 moles S 1 mole
= 9.89 x 10²³ molecules H₂S
