Question

How many grams of NaOH is produced from `1.20 x 10^2` grams of `Na_2O`? `Na_2O + H_2O -> 2NaOH`

Answer 1

If we begin the problem with 120. grams of `Na_2O` and we are trying to find the mass of `NaOH` that can be produced, this is a gams to grams stoichiometry problem.

`grams -> mols -> mols -> grams`

`120. g Na_2O` x `(1 mol Na_2O) / (62. g Na_2O)` x `(2 mol NaOH) / (1 mol Na_2O)` x `(40. g NaOH) / (1 mol NaOH)` =

the gfm of `Na_2O` is (2 x 23 + 1 x 16 = 62)
the gfm of `NaOH` is (1 x 23 + 1 x 16 + 1 x 1 = 40)

The mole ratio from the balanced chemical equation is 2 moles of `NaOH` for every mole mole of `Na_2O`.

The final calculation is
120 x 2 x 40 / 62 = 154.8387

The final solution comes to `154. grams NaOH`

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