Question

The molar mass of monopotassium phosphate is 136.09 g/mol. How many moles of monopotassium phosphate are needed to make 250.0 ml of 0.15 M monopotassium phosphate?

Answer 1

0.0375 moles

Step-by-step explanation:

Given that:

Molar mass of monopotassium phosphate = 136.09 g/mol

Given that volume = 250.0 mL

Also,

`1\ mL=10^(-3)\ L`

So, Volume = 250 / 1000 L = 0.25 L

Molarity = 0.15 M

Considering:

`Molarity=(Moles\ of\ solute)/(Volume\ of\ the\ solution)`

`0.15=(Moles\ of\ solute)/(0.25)`

Thus, moles of monopotassium phosphate needed = 0.0375 moles