Answer:
0.0953M
Explanation:
First, let us calculate the number of mole present in 12.5g of Na2CrO4.
Molar Mass of Na2CrO4 = (23x2) + 52 +(16x4) = 46 + 52 +64 = 162g/mol
Mass of Na2CrO4 = 12.5g
Number of mole =?
Number of mole =Mass /Molar Mass
mole of Na2CrO4 = 12.5/162 = 0.0772mol
Now, we can calculate for the molarity as follows:
Mole = 0.0772mol
Volume = 810mL = 810/1000 = 0.81L
Molarity =?
Molarity = mole /Volume
Molarity = 0.0772mol/0.81L
Molarity = 0.0953M