Answer:
2.25 M
Explanation:
Molarity of a substance , is the number of moles present in a liter of solution .
M = n / V
M = molarity
V = volume of solution in liter ,
n = moles of solute ,
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the question ,
w = given mass of Nal = 76 g
and ,
V =volume of solution = 225.0 mL
since ,
1 mL = 1 / 1000 L
V = 225.0 / 1000 L = 0.225 L
Since ,
we know ,
m = Molecular mass of NaI = 149.89 g / mol
using , the above formula to calculate the moles ,
n = w / m = 76 g / 149.89 g/mol = 0.507 mol
now , calculating the molarity as ,
M = n / V = 0.507 mol / 0.225 L = 2.25 M