Question

What are the molarity and the normality of a solution made

bydissolving 25g of of citric acid(C6
H5O7 H3 ,a triprotic acid) in
enough water tomake 750 mL of solution?

Answer 1

Step-by-step explanation:

It is known that molarity is the number of moles present in a liter of solution.

Mathematically, Molarity =
`\frac{\text{no. of moles}}{\text{volume in liter}}`

Hence, calculate the molarity of given solution as follows.

Molarity of citric acid =
`\frac{\text{mass of citric acid}}{\text{molar mass of citric acid}} * \frac{1}{\text{volume of solution(L)}}`

=
`(25 g)/(192.13 g/mol) * (1)/(0.75 L)`

= 0.173 M

As citric acid is a triprotic acid so, upon dissociation it gives three hydrogen ions.

Normality = Molarity × no. of hydrogen or hydroxide ions

= 0.173 × 3

= 0.519 N

Thus, we can conclude that molarity of given solution is 0.173 and its normality is 0.519 N.