If 20.00 mL of 0.2019 M HCl requires 39.63 mL of a NaOH solution for complete neutralization, what is the concentration of the NaOH solutions? How many significant figures are justified in the answer?

Answer 1

The equation is
HCl + NaOH ==> NaCl + H2O

mols HCl = M x L
Convert mols HCl to mols NaOH from the equation.
M(NaOH) = #mols/L.
You have mols and L, solve for M.
Post your work if you get stuck.

Answer 2

.1019M NaOH 4 sig figs

Answer 3

HCl + NaOH ==> NaCl + H2O

(Don't forget to convert mL to L)

.2019M HCl = mol/L
solve for mol
Answer mol HCL = .02L * .2019M

1-1 ratio based on equation: (Answer mol HCL/1) * (1 mol HCL/ 1 mol KHP) = Answer mol HCl

using molarity equation, mol/L = M
solve for M
Answer mol HCL/ .03963 L = Final Answer M NaOH

Answer 4

** Correction**

HCl + NaOH ==> NaCl + H2O

(Don't forget to convert mL to L)
(Use M=(mol/L)

.2019M HCl = mol/L
solve for mol
Answer mol HCL = .02L * .2019M

1-1 ratio based on equation: (Answer mol HCL/1) * (1 mol NaOH/ 1 mol HCl) = Answer mol NaOH

using molarity equation, mol/L = M
solve for M
Answer mol NaOH/ .03963 L = Final Answer M NaOH