What is an example of a neutralization practice problem?

1 Answer
May 7, 2014

What is the concentration of sodium hydroxide if it takes 43.21 mL of sodium hydroxide to neutralize 25.00 mL of 0.273 M hydrochloric acid?

For this problem we are looking for the concentration of Molarity of the base in a neutralization reaction.

Using the balanced chemical equation

#HCl + NaOH -> H_2O + NaCl#

The reaction uses one mole of sodium hydroxide for every one mole of hydrochloric acid.

The equation for equilibrium of a neutralization reaction is

#n_bM_aV_a = n_aM_bV_b#

#n_a# = moles of acid
#n_b# = moles of base
#M_a# = Molarity of Acid
#V_a# = Volume of Acid
#M_b# = Molarity of Base
#V_b# = Volume of Base

#n_a# = 1 mole
#n_b# = 1 mole
#M_a# = 0.273 M
#V_a# = 25.00 mL
#M_b# = ???
#V_b# = 43.21 mL

#1 mol (0.273 M)(25.00 mL) = 1 mol (x M)(43.21 mL)#
#(6.825 M mL)/(43.21mL) = x M#
#0.158 M = x#

I hope this was helpful.
SMARTERTEACHER