Question

Which of the following samples contains the largest total number of atoms? Please show work

a) 0.10 moles of P4O10

b) 0.20 moles of P4O6

c) 0.30 moles of N2O5

d) 0.40 moles of N2O4

e) 0.50 moles of BiF3

Answer 1

a) 0.10 moles of P₄O₁₀

1 molecule of P₄O₁₀ contains 4 P & 10 O atoms, a total of 4+10 = 14 atoms

we know that 1 mole contains Avagadro number ( N = 6.023x 10 ²³ atoms) of atoms

1.0 mol of P₄O₁₀ contains 14 x N atoms

0.10 mol of P₄O₁₀ contains 0.10x 14 x N atoms = 1.4 N atoms

b) 0.20 moles of P₄O₆

1 molecule of P₄O₆ contains 4 P & 6 O atoms, a total of 4+6 = 10 atoms

we know that 1 mole contains Avagadro number ( N = 6.023x 10 ²³ atoms) of atoms

1.0 mol of P₄O₆ contains 10 x N atoms

0.20 mol of P₄O₁₀ contains 0.20x 10 x N atoms = 2.0 N atoms

c) 0.30 moles of N₂O₅

1 molecule of N₂O₅ contains 2 N& 5 O atoms, a total of 2+5 = 7 atoms

we know that 1 mole contains Avagadro number ( N = 6.023x 10 ²³ atoms) of atoms

1.0 mol of N₂O₅ contains 7 x N atoms

0.30 mol of N₂O₅ contains 0.30x 7 x N atoms = 2.1 N atoms

d) 0.40 moles of N₂O₄

1 molecule of N₂O₄ contains 2 N& 4 O atoms, a total of 2+4 = 6 atoms

we know that 1 mole contains Avagadro number ( N = 6.023x 10 ²³ atoms) of atoms

1.0 mol of N₂O₄ contains 6 x N atoms

0.40 mol of N₂O₄ contains 0.40x 6 x N atoms = 2.4 N atoms

e) 0.50 moles of BiF₃

1 molecule of BiF₃ contains 1 Bi & 3 F atoms, a total of 1+3 = 4 atoms

we know that 1 mole contains Avagadro number ( N = 6.023x 10 ²³ atoms) of atoms

1.0 mol of BiF₃ contains 4 x N atoms

0.50 mol of BiF₃ contains 0.50 x 4 x N atoms = 2.0 N atoms

Therefore (d) 0.40 moles of N₂O₄ contains largest number of atoms