Acid-Base problem, HELP?
What volume of .230 M H3PO4 will react completely with 50.52ml of 0.133 M NaOH?
i am studying for a test right now and i keep getting 97.37 but it's incorrect in the back of my textbook. please help, thank you
What volume of .230 M H3PO4 will react completely with 50.52ml of 0.133 M NaOH?
i am studying for a test right now and i keep getting 97.37 but it's incorrect in the back of my textbook. please help, thank you
Comments
H3PO4 is a tribasic acid and thus it would leave 3 hydrogen ions on complete dissociation in solution but NaOH is a monoacidic base because it contains only one OH group. Thus when u r mixing the above reactants the concentration of H3PO4 actually becomes (.23*3) because it liberates 3 H+ ions..Now use the molarity equation: M1V1=M2V2 put the concentration of H3PO4 as (.23*3) and u will obviously get the result
First, balance the eqn
3NaOH + H3PO4 = Na3PO4 + 3 H20
Figure out how many moles of NaOH you have:
n(NaOH) = 50.52 mL * (0.133 mol / L) = 0.05052 L * (0.133 mol / L )
n(NaOH) = 0.006719 mol
Since need 3 (NaOH) to 1 H3PO4, then n(H3PO4)=n(NaOH)/3
n(H3PO4)= 0.00223972 mol
If you have a soln of .230 M of H3PO4, then you need
V = n(H3PO4) / (.230M) = (0.0097379) L = 9.738 mL