Question

What mass of Na2CO3 is required to create 750 mL of an aqueous solution where the concentration of the carbonate (CO3-2) ions is 1.75 M? (assume complete dissociation)

Answer 1

139.11 grams

Step-by-step explanation:

The molarity (M) is equal to m (moles) /L (liters).

Notice how it is in mL so converting it would be 0.75 L (750*10-3)

Now plug in the information

1.75=m/0.75

m=1.3125

Now m is in moles so convert to grams to get the mass

1.3125 mol Na2CO3 * 105.9888 g Na2CO3 = 139.1103