Question

A solution is made by dissolving 74.5 g KNO3 in water to make 700.0 mL of solution. What is the molarity of the solution?

Answer 1

Answer:1.04M

Step-by-step explanation:

Molarity is defined as the ratio of number of moles of solute per litre of solution.

Let molarity be
`M`.

Given mass of
`KNO_(3)`
`=74.5g`

Weight of
`K` is
`39g`

Weight of
`N` is
`14g`

Weight of
`O` is
`16g`

Molar mass of
`KNO_(3)=39+14+3(16)=101g`

Let
`n` be the number of moles of solute.

`n=(given mass)/(molar mass)=(74.5)/(101)=0.73`

Let
`v` be the volume of solution.

Given,
`v=700mL=0.7L`

`M=(n)/(v)`
`=(0.73)/(0.7)=1.04M`