Chemistry project homework help with mols and atoms and dimensional analysis?

Question

Its for a chemistry project, I need help, my teacher hasnt been in class for the last week, so I have absolutely no idea what "mol" is.

Here are the exact steps:
1. Cut out 3 nutrition facts labels from three different foods. One should be high in sodium compared to the others.
2. Look for the total grams of "Sodium" per serving.
3. Using dimensional analysis, show haow many moles and atoms of sodium you are eating for one serving.
4. How many servings of food would you have to eat in order to reach the maximum daily recommended amount of sodium.

Ive got the three labels, they are:

1. Frozen Waffles - 480mg of sodium - 20% daily value 2.Gatorade - 110mg of sodium - 5% daily value
3.Juice - 35mg of sodium - 1% daily value.

Answer 1

Using dimensional analysis is simply using fractions to cancel out measurement units. The mass of Na is 23 amu, so 23 g Na = 1 mol Na.

480 mg / 1 X 1 g / 1000 mg X 1 mol Na / 23 g Na = ?

mult numerators, then denominators and divided the two answers: (480 mg)(1 g)(1 mol) / (1)(1000 mg)(23 g) = ?

Use this same format when working the rest. Just substitute 110 mg instead of 480 mg, then 35 mg.