Question

A 0.1090 g sample of copper metal is dissolved in 60. ml of concentrated hno3 to form cu2+ ions and then water is added to make a total volume of 203.1 ml. (calculate the molarity of cu2+.)

Answer 1

Mass of Copper metal dissolved = 0.1090 g

Moles of Copper dissolved =
`0.1090 g * (1 mol)/(63.55 g) = 0.00172 mol Cu`

Total volume of the solution = 203.1 mL
`* (1 L)/(1000 mL) = 0.2031 L`

Calculating the molarity of copper ions in the solution:

Molarity of a solution =
`(Moles of solute)/(Volume of solution (L))`

=
`(0.00172 mol Cu^(2+))/(0.2031 L)`

=0.00845 mol/L

Therefore the molarity of copper ions is 0.00845 mol/L