How many moles of Na2SO4 are present in 284.078 grams of Na2SO4?
A. 2
B. 3
C. 5
D. 6

It’s A. 2
Explanation:
First step: find out how many grams are in one mole of Na2SO4
Multiply the number of atoms by the mass of the element
Na: 2 * 23 = 46 units
S: 1 * 32 = 32 units
O: 4 * 16 = 64 units
Add them all together
142 g/mol
Now set up the table

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