Question

a. How many ATOMS of carbon are present in 3.13 moles of carbon tetrabromide ? ------ atoms of carbon.

b. How many MOLES of bromine are present in 1.60×1021 molecules of carbon tetrabromide ? ----- moles of bromine.

c. How many ATOMS of sulfur are present in 3.88 moles of sulfur dioxide ? ------ atoms of sulfur.

d. How many MOLES of oxygen are present in 6.72×10²² molecules of sulfur dioxide ? ------- moles of oxygen.

e. How many MOLECULES of carbon tetrachloride are present in 4.93 moles of this compound ? ----- molecules.

f. How many MOLES of carbon tetrachloride are present in 4.53×10²² molecules of this compound ? ----- moles.

Answer 1

a).

moles of CBr4 = 3.13 mol

1 mol ---------------> 6.023 x 10^23 atoms

3.13 mol --------------->   ??

number of Carbon atoms = 3.13 x 6.023 x 10^23

                                        = 1.88 x 10^24 atoms

b).

1 mol ---------------> 6.023 x 10^23 molecules

?? mol ---------------> 1.60×10^21 molecules

number of moles = 1.60×10^21 / 6.023 x 10^23

                             = 2.66 x 10^-3 mol

moles of CBr4 = 2.66 x 10^-3 mol

moles of bromine = 0.0106 mol

c.)

atoms of SO2 = 3.88 x 6.023 x 10^23

atoms of S = 2.34 x 10^24 atoms

d.

moles of SO2 = 6.72×10²² / 6.023 x 10^23

                      = 0.112

moles of oxygen = 0.223