If you were given the the total # of grams of all three compounds with the % of each molecular compound - H2O, CO2 and sugar [you would need to know the type of sugar in the Pop such as C12H22O11 as to find its MM (molar mass)]
To begin take the % of each compound x the total grams of all the compounds. For illustrative purposes let's say it works out to be 50 grams of H2O in the POP. The same would be. done for CO2 and for the sugar.
Step 1) With the mass of each you could determine the # of moles of each:
Example if the number grams of water in the sample is 50g, to determine the # of moles of water you would do the following - 50g H20 x 1 mol/18g H20 = 2.8 mol H2O The same technique would be used for the other compounds to find the # of moles.
Step 2) To find the representative particles of each(molecules, atoms) you would do the following:
as the example given of above for H20 - 50 grams you calculated as shown above to be the number of mol of H20 = 2.8mol
From the number of mol of H20, to determine the # of molecules of water you would set up the following:
2.8 mol H20 x 6.02 x 10^23/1 mol H2O = 1.69 X 10^24 molecules of H20.
The same would be done for CO2 and the sugar.
Step 3) Now to find the number of atoms of element of the compound taking for example the H2O example above:
Take the # of molecules of H2O found above and set it up in the following manner:
1.69 X 10^24 molecules H2O x 2 atoms H/1 molecule H2O = 3.38 x 10^24 atoms H
1.69 x 10^24 molecules H2O x 1 atom O)/1 molecule H2O = 1.69 X 10^24 atoms O
The same would be done for CO2 and for the sugar compound.