What mass of sodium hydroxide (#NaOH#) is contained in 250#cm^3# of 0.02M sodium hydroxide solution?

1 Answer
Jan 11, 2017

Answer:

Approx. #200*mg#.

Explanation:

#"Concentration"# #=# #"Moles of solute"/"Volume of solution"#.

And thus #"Moles of solute"="Volume of solution"xx"concentration"#.

And thus #"Moles of NaOH"=250*cancel(cm^3)xx10^-3cancelL*cancel(cm^-3)xx0.02*mol*cancel(L^-1)=5.0xx10^-3*mol.#

#"Mass"="moles"xx"molar mass"=5.0xx10^-3*cancel(mol)xx40.0*g*cancel(mol^-1)=??g#