Question

If 3.0 moles H2S and 1.0 mole SO2 react according to the following equation, how many moles of water will form? Reaction: 2H2S + SO2 → 3S + 2H2O

Answer 1

Answer: 2 moles of
`H_2O` will be formed.

Explanation: Reaction in the given question is :

`2H_2S+SO_2\rightarrow 3S+2H_2O`

Number of moles of
`SO_2` = 1 mole

Number of moles of
`H_2S` = 3 moles

Here, the excess reagent is
`H_2S` because its number of moles are more and
`SO_2` is the limiting reagent as its number of moles are less.

So, the amount of
`H_2O` produced will depend on the the amount of
`SO_2` used.

By stoichiometry, one molecule of
`SO_2` produces 2 molecules of
`H_2O`.

Therefore, 1 mole of
`SO_2` will produce 2 moles of
`H_2O`.