How many molecules of BH3 are in 14.32 grams of BH3?

6.23 x 10^23 molecules

Explanation:

First find the number of moles of BH3 from the information given. We know the amount of grams present and we can find the molar mass which is 13.84.

We know that moles is grams divided by molar mass so we get 14.32/13.84 which is 1.03 moles.

Finally, to figure out the number of molecules, we multiply 1.03 by Avogadro's number which is 6.022x10^23 and we get 6.23x10^23 molecules.