Question

What will be the molarity of a solution in which 84.5 grams of KNO, are dissolved in 750.0 ml of solution

Answer 1

Molar mass of KNO3

`\\ \large\sf\longmapsto KNO_3`

`\\ \large\sf\longmapsto 39u+14u +3(16u)`

`\\ \large\sf\longmapsto 53u+48u`

`\\ \large\sf\longmapsto 101u`

`\\ \large\sf\longmapsto 101g/mol`

• Given mass=84.5g

`\boxed{\sf No\:of\:moles=(Given\:mass)/(Molar\:Mass)}`

`\\ \large\sf\longmapsto No\:of\:moles=(84.5)/(101)`

`\\ \large\sf\longmapsto No\:of\:moles=0.8mol`

Now

`\boxed{\sf Molarity=(Moles\:of\:solute)/(Volume\:of\:solution\;in\;L)}`

`\\ \large\sf\longmapsto Molarity=(0.8)/(0.750L)`

`\\ \large\sf\longmapsto Molarity=1.06M`