Question

The molarity of a 4.200 L solution is 1.230 M Na2CO3. What is the mass of Na2CO3

within the solution?

Answer 1

547.5g

Step-by-step explanation:

To get the mass, you need moles.

moles = (molarity)(Liters)

moles = (1.230M)(4.200L) = 5.166 moles Na2CO3

Now, just use stoichiometry

molar mass of Na2CO3 = 2(mass of Na) + (mass of C) + 3(mass of O)

= 2(22.9) + 12.01 + 3(16) = 105.99g/mol

5.166moles(105.99g/mol)

= 547.544

But, the measurements given had 4 significant figures, so in chemistry we write:

547.5g