Question

Calculate the mass of oxalic acid dihydrate needed to prepare 500.0 ml

Answer 1

moles= molarity x liter
=0.2500 M x 0.500 L
= 0.1250 mol

mass C2H2O4 . 2H2O = 0.1250 mol x (126.068 g / 1 mol)
=15.76 g

Answer 2

This question is incomplete.

The complete question is: Calculate the mass of oxalic acid dihydrate
`C_2H_6O_6.2H_2O` needed to prepare 500.0 mL of 0.2500 M oxalic acid solution.

Answer: 15.75 grams

Step-by-step explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

`Molarity=(n* 1000)/(V_s)`

where,

Molarity = 0.2500 M

n= moles of solute = ?

`V_s` = volume of solution in ml = 500.0 ml

`0.2500=(n* 1000)/(500.0)`

`n=0.1250`

Mass of oxalic acid dihydrate =
`moles* {\text {Molar Mass}}=0.1250* 126.07g/mol=15.75g`

Therefore, the mass of oxalic acid dihydrate needed to prepare 500.0 ml is 15.75 grams