How many nitrogen atoms are there in 51.0 g of (NH₄)₂SO₄ (ammonium sulfate)? A)2.32 10²³ atoms B)3.07 10²⁵ atoms C)4.65 10²³ atoms D)6.14 10²⁵ atoms E)5.39 10²³ atoms

Question

Quizplus · Accepted Answer

1) Find the molar mass of ammonium sulfate: 
N: 2 x 14.01 = 28.02 g/mol 
H: 8 x 1.01 = 8.08 g/mol 
S: 1 x 32.06 = 32.06 g/mol 
O: 4 x 16.00 = 64.00 g/mol 
Total: 132.16 g/mol

2) Calculate the number of moles of ammonium sulfate using the formula: 
moles = mass/molar mass

moles = 51.0 g / 132.16 g/mol = 0.386 moles

3) Calculate the number of nitrogen atoms using the formula: 
number of atoms = moles x Avogadro's number x number of atoms in one molecule

number of atoms = 0.386 x 6.022 x 10^23 x 2 = 4.65 x 10^23

Therefore, the answer is C.

How Many Nitrogen Atoms Are There in 51