Question

Standardization of a Borax solution (Na2B4O7). You are given a 1.044 M solution of H2SO4. It takes 2.63 mL of this H2SO4 to reach the end point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?

Answer 1

The question is incomplete, the complete question is:

Standardization of a Borax solution (Na2B4O7). A student titrates a 20.00 mL sample of an aqueous borax solution with 1.044 M H2SO4. It takes 2.63 mL of acid to reach the equivalence point. Knowing it takes 1 H2SO4 to neutralize 2 Na2B4O7, what was the concentration of this Borax solution?

Answer: The concentration of borax solution is 0.069 M.

Explanation:

To calculate the concentration of borax solution, the formula used is:

$n_1C_1V_1=n_2C_2V_2$ ....(1)

where,

$n_1, C_1\text{ and }V_1$ are the n-factor, concentration and volume of sulfuric acid

$n_2,C_2\text{ and }V_2$ are the n-factor, concentration and volume of borax solution.

We are given:

$n_1=1\\C_1=1.044M\\V_1=2.63mL\\n_2=2\\C_2=?M\\V_2=20mL$

Putting values in equation 1, we get:

$1\times 1.044\times 2.63=2\times C_2\times 20\\\\C_2=\frac{1\times 1.044\times 2.63}{2\times 20}\\\\C_2=0.069M$

Hence, the concentration of borax solution is 0.069 M.