CHEMISTRY 101 EXAMPREP REVIEW SHEET WITH TESTED QUESTIONS AND COMPLETE SOLUTIONS

CHEMISTRY 101 EXAMPREP REVIEW SHEET
WITH TESTED QUESTIONS AND COMPLETE
SOLUTIONS

●● Avogadro's number
Answer: 6.022 X 10²³ particles or 1 mole


●● Molar Mass (MM)
Answer: The average mass of an atom of any substances as the mass of
1 mole.
ex. Carbon is 12.01 g/mol
ex. Oxygen is 16.00 g/mol
CO₂ is 44.01 g/mol


●● Mass in grams X molar mass
Answer: equals moles


●● Moles X molar mass
Answer: equals mass in grams


●● 1 mole
Answer: 6.022 X 10²³

, ●● Empirical formula
Answer: Expresses the simplest ratio of atoms in a compound and
written with the smallest whole-number subscripts. ex. C₅H₁₀ → CH²


●● Molecular formula
Answer: Expresses the actual number of atoms in a compound and can
have the same subscripts as the empirical formula or some multiple of
them.


●● Finding Empirical
Answer: 1. Assume any size sample is 100 grams so % value =mass
value.
2. Convert grams to moles for each element using its molar mass as a
conversion factor.
3. Without changing the relative amounts, change moles to whole
numbers. Do this by dividing all by the same smallest value. If all do not
convert to whole numbers, multiply to get whole numbers


●● Percent Mass Solute (solution concentration formula)
Answer: (mass of solute / total mass of solution) X 100


●● Concentration
Answer: Ratio of solute to solvent