Question

how many moles of sodium are there in 28.4 grams of na2so4?

Answer 1

Find the molar mass of \[\text{Na}_2\text{SO}_4\]Then, divide mass by that molar mass to get the number of moles.

Answer 2

yes but doesn't that give us the moles for Na2SO4? How do we find the amount of moles Sodium has in this case?

Answer 3

There are two atoms of sodium in each molecule of sodium sulfate. Once you have the number of moles of sodium sulfate, multiply by two.

Answer 4

28.4g/142.04g = 0.19999mol. the answer is 0.20mol.

Answer 5

on the page the answer is 0.20mol

Answer 6

Trust your instincts on this. Often the answers in books are wrong. Ask your teacher about this to see if there is a mistake in the book.

Answer 7

ok thanks for your help!