Question

Question #a5115

Answer 1

Use its molar mass!

Explanation:

Let's say that you're dealing with a generic reaction

`"A " + " 2B " -> " C"`

Notice that you have a `1:1` mole ratio between `"A"` and `"C"`. This tells you that the reaction will consume a number of moles of `"A"` and produce the same number of moles of `"C"`.

So, let's say that the reaction consumes `3` moles of `"A"`. The `1:1` mole ratio tells you that it will produce `3` moles of `"C"`.

To convert the number of moles of `"C"` to grams, use its molar mass. Let's say that `"C"` has a molar mass of `x` `"g mol"^(-1)`.

This means that `1` mole of `"C"` has a mass of `x` grams. You can thus say that the reaction produced

`3 color(red)(cancel(color(black)("moles C"))) * overbrace((x color(white)(.)"g")/(1color(red)(cancel(color(black)("mole C")))))^(color(blue)("the molar mass of C")) = (3x)" g"`

of the product, i.e. `(3x)` `"g"` of `"C"`.