Question

A student weighs out 3.32 g of Co(CH3COO)2, transfers it to a 125. mL volumetric flask, adds enough water to dissolve the solid and then adds water to the 125 mL mark on the neck of the flask.

Calculate the concentration (in molarity units) of cobalt(II) acetate in the resulting solution?

M

Answer 1

$n=m/M$

$n(Co(CH_3COO)_2)=3.32g/(177g/mol)=0.01875mol$

$C=n/V$

$C(Co(CH_3COO)_2)=0.01875mol/0.125L=$$0.15M$

The answer is 0.15 M