Chapter 3, Problem 86IAE

The important natural sources of boron compounds are the minerals kernite, ${\text{Na}}_{\text{2}}{\text{B}}_{\text{4}}{\text{O}}_{\text{t}}\cdot {\text{4 H}}_{\text{2}}\text{O}$ and borax, ${\text{Na}}_{\text{2}}{\text{B}}_{\text{4}}{\text{O}}_{\text{t}}\cdot {\text{10 H}}_{\text{2}}\text{O}\text{.}$ How much additional mass of mineral must be processed per kilogram of boron obtained if the mineral is borax rather than kernite?