Question

62 grams of Zn(C2H3O2)4 are dissolved to make a 1.5 M solution. How many milliliters of water are needed?

Answer 1

If the molar mass is 301.5561 then we will next need to find the moles.

Mol = Mass (g) / Molar Mass

Mol = 62 g / 301.5561

Mol = .2056

# of Mol / # of Liters = Solution

.2056 / X = 1.5

x is the # of Liters

.137 Liters

To move change a number from liters to mililiters we have to move the decimals point 3 places to the right.

Now the answer is 137 ML

Answer 2

molarmass of Zn(C2H3O2)4 is 301.5561 g/mol

moles of
Zn(C2H3O2)4
= 62 g * 1 mol/(301.5561 g) = 0.2056 mol

concentration = moles / volume
concentration * volume = moles
volume = moles / concentration
volume = 0.2056 mol / 1.5 M
volume = 0.13706 L
volume = 137 mL
volume = 140 mL