Molar mass of the salt from \( \mathrm{NaBr} \), \( \mathrm{NaNO_3} \), \( \mathrm{KI} \) and \( \mathrm{CaF_2} \) which does not evolve coloured vapours on heating with concentrated \( \mathrm{H_2SO_4} \) is ______ \( \mathrm{g \, mol^{-1}} \).
(Molar mass in \( \mathrm{g \, mol^{-1}} \): \( \mathrm{Na}: 23 \), \( \mathrm{N}: 14 \), \( \mathrm{K}: 39 \), \( \mathrm{O}: 16 \), \( \mathrm{Br}: 80 \), \( \mathrm{I}: 127 \), \( \mathrm{F}: 19 \), \( \mathrm{Ca}: 40 \))