How many grams in 3.75 mol of NaBr?

1 Answer
Feb 20, 2016

"386 g"

Explanation:

You can find how many grams would be equivalent to 3.75 of sodium bromide, "NaBr", by using the mass of one mole of this ionic compound.

As you know, the mass of one mole of a compound is expressed by that compound's molar mass. Sodium bromide has a molar mass "102.9 g mol"^(-1), which means that one mole of sodium bromide has a mass of "102.9 g".

You can thus use the molar mass of a compound to convert between its mass and the number of moles equivalent to that mass. In your case, you will have

3.75 color(red)(cancel(color(black)("moles NaBr"))) * overbrace("102.9 g"/(1color(red)(cancel(color(black)("mole NaBr")))))^(color(purple)("molar mass")) = "385.875 g"

You need to round this off to three sig figs, the number of sig figs you have for the number of moles of sodium bromide

m_(NaBr) = color(green)("386 g")