Question

The densevapor iodinee heptafluoride reacts rapidly with water to give a mixture of periodic acid and hydrofluoric acid .

Answer 1

Explanation:

When iodine heptafluoride reacts rapidly with water to give a mixture of periodic acid and hydrofluoric acid. Reaction equation for the same is as follows.

       $IF_{7} + 6H_{2}O \rightarrow H_{5}IO_{6} + 7HF$

As it is given that there are $3.72 \times 10^{-2}$ moles of iodine heptafluoride are present. Molar mass of $IF_{7}$ is 259.9 g/mol. Molar mass of $HIO_{4}$ is 227.94 g/mol and molar mass of HF is 20.01 g/mol.

Now, according to the reaction equation $3.72 \times 10^{-2}$ M $IF_{7}$ gives $3.72 \times 10^{-2}$ M $H_{5}IO_{6}$.

Also, the volume is given as 795 ml or 0.795 L (as 1 mL = 0.001 L).

Hence, calculate the concentration of $H_{5}IO_{6}$ into the solution as follows.

              Concentration = $\frac{\text{no. of moles}}{volume}$

                                      = $\frac{3.72 \times 10^{-2}}{0.795 L}$

                                      = $4.7 \times 10^{-2}$ mol/L

or,                                   = 0.047 M

Now, as 1 mol of $IF_{7}$ produces 7 mol HF. So, $7 \times 3.72 \times 10^{-2} = 26.04 \times 10^{-2}$ M HF.

Therefore, concentration of HF will be calculated as follows.

             Concentration of HF = $\frac{0.2604}{0.795}$

                                              = 0.33 M

Thus, we can conclude that concentration of periodic acid is 0.047 M and concentration of hydrofluoric acid is 0.33 M.