Finding moles of NO3- ion

March 27th, 2009

How many moles of NO3- ions are present in 220 mL of a 0.515 M Al(NO3)3 solution.?

The Chemistry answer

Al(NO3)3 will dissociate in solution to be:

Al(NO3)3 -> Al3+ + 3NO3-

from the reaction we know that one mole of Al(NO3)3 will produces 1 mole of Al3+ and 3 moles of NO3- ions. Thus we should find moles of Al(NO3)3 to find out moles of NO3-.

moles Al(NO3)3
= M x V
= 0.515 M x 220 mL
= 113.3 mmol

thus moles of NO3-
= 3 x mol Al(NO3)3
= 3 x 113.3 mmol
= 339.9 mmol

Entry Filed under: Chemical Equation