How many moles are in 550.0 g of lead(II) sulfate?

1 Answer
Mar 6, 2017

Answer:

#"1.814 moles PbSO"_4#

Explanation:

You can go from moles of a given substance to grams or vice versa by using the molar mass of said substance.

The molar mass tells you the mass of #1# mole of a given substance

#"molar mass" = "mass in grams"/"1 mole of substance"#

In your case, lead(II) sulfate, #"PbSO"_4#, has a molar mass of #"303.2626 g mol"^(-1)#, which means that every mole of lead(II) sulfate has a mass of #"303.2626 g"#.

To convert from grams to moles, set up the molar mass as a conversion factor with the mass of #1# mole as the denominator

#"1 mole PbSO"_4/"303.2626 g"#

You will have

#550.0 color(red)(cancel(color(black)("g"))) * "1 mole PbSO"_4/(303.2626color(red)(cancel(color(black)("g")))) = color(darkgreen)(ul(color(black)("1.814 moles PbSO"_4)))#

The answer is rounded to four sig figs.