Question

3H2(g)+N2(g)?2NH3(g)

How many molecules (not moles) of NH3 are produced from 5.41

Answer 1

N2 + 3H2 ---> 2NH3

moles = mass / molar mass
molar mass H2 = 2 x 1.008 = 2.016 g/mol
moles H2 = 5.41 x 10^-4 g / 2.016 g/mol
= 2.68 x 10^-4 moles H2

Equation shows that 3 moles H2 form 2 moles NH3
Therefore 1 mole H2 -----> 2/3 moles NH3
and 2.68 x 10^-4 moles H2 -----> (2/3 x 2.68 x 10^-4) moles NH3

= 1.787 x 10^-4 moles of NH3 produced from the H2

Now, 1 mole of any molecule contains 6.022 x 10^23 molecules

SO Number of molecules = moles x avagadros number

molecues of NH3 = 1.787 x 10^-4 moles x 6.022x10^23
= 1.076 x 10^20 molecules of NH3 are produced