Question

Describe a situation in which you might find yourself where you would need to perform an immediate titration. Think hard. This should be a solid paragraph answer.

Answer 1

Titration is a technique in analytical chemistry used to find an unknown concentration of an analyte by reacting it with a known volume and concentration of a standard solution (called the titrant). Titrations are typically used for acid-base reactions and redox reactions.

To find concentration of the HCl ? if a 25 ml solution of 1.0 M NaOH is titrated until neutralized into a 50 ml sample of HCl ?

Step-by-Step Solution

Step 1 - Determine [OH^-]

Every mole of NaOH will have one mole of OH^-. Therefore [OH^-] = 1 M.

Step 2 - Determine the number of moles of OH^-

Molarity = # of moles/volume

# of moles = Molarity x Volume

# of moles OH^- = (1 M)(.025 L)
# of moles OH^- = 0.025 mol

Step 3 - Determine the number of moles of H⁺

When the base neutralizes the acid, the number of moles of H⁺ = the number of moles of OH^-. Therefore the number of moles of H⁺ = 0.025 moles.

Step 4 - Determine the concentration of HCl

Every mole of HCl will produce one mole of H⁺, therefore the number of moles of HCl = number of moles of H⁺.

Molarity = # of moles/volume

Molarity of HCl = (0.025 mol)/(0.050 L)
Molarity of HCl = 0.00125 M

Answer

The concentration of the HCl is 0.00125 M.

Another Solution Method

The above steps can be reduced to one equation

M_acidV_acid = M_baseV_base

where

M_acid = concentration of the acid
V_acid = volume of the acid
M_base = concentration of the base
V_base = volume of the base

M_acidV_acid = 2M_baseV_base