Question

Question #c8464

Answer 1

`"10. g"`

Explanation:

You can go from moles of sodium hydroxide, `"NaOH"`, to grams of sodium hydroxide by using a conversion factor called molar mass.

The molar mass tells you the mass of exactly one mole of a given substance. In this case, sodium hydroxide has a molar mass of `"39.997 g mol"^(-1)`, which implies that one mole of sodium hydroxide has a mass of `"39.997 g"`.

You can thus use the molar mass of sodium hydroxide to calculate how many grams you'd get in `0.25` moles of this compound

`0.25 color(red)(cancel(color(black)("moles NaOH"))) * "39.997 g"/(1color(red)(cancel(color(black)("mole NaOH")))) = color(green)(|bar(ul(color(white)(a/a)color(black)("10. g")color(white)(a/a)|)))`

The answer is rounded to two sig figs, the number of sig figs you have for the number of moles of sodium hydroxide.