Calculate the molarity of a solution prepared by dissolving 12.5 g of Na2CrO4 in enough water to produce a solution with a volume of 810. mL .

Respuesta :

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