How many molecules are in 25.0 grams of NH3?

Question

Please answer my question correctly with steps

Answer 1

The first step is to determine the number of moles the 25 grams of NH₃ is. Then we can use Avogadro's number to convert moles to number of molecules.

To convert 25 grams to moles, we need the molar mass.

N = 14.007 g/mol

H = 1.008 g/mol x 3 = 3.024 g/mol

So NH₃ = 14.007 + 3.024 = 17.031 g/mol

(25 g NH₃)/(17.031 g/mol NH₃) = 1.4679 moles NH₃

There are 6.022 x10²³ molecules/mole so (6.022 x10²³ molecules/mole) x (1.4679 moles NH₃) = 8.84 x 10²³ molecules in 25.0 grams of NH₃