Mole Conversions, Empirical and Molecular Formulas Review

The Mole

100

How is a mole similar to a dozen?

They both measure groups of items in set quantities.

200

What is Avogadro's number?

6.02 x 10²³

300

How many atoms are in one mole of Sodium Chloride?

6.02 x 10²³

400

How many moles of hydrogen are in one mole of water? H₂O

2

500

How many moles of sodium are in one mole of Na₃(PO)₂?

3

Empirical Formulas

100

If this is the molecular formula; what should be the empirical formula of H₂O₂ ?

H₁O_{1 or} HO

200

Determine the empirical formula of a compound containing 54.2%F and 45.8% S.

SF₂

300

A compound is 40.0 % carbon, 53.3 % oxygen, and 6.66 % hydrogen. What is its empirical formula?

COH₂

400

This is the empirical formula for a compound that has 48.0% C, 4.0% H and 48.0% O.

C₄H₄O₃

500

What should be the empirical formula of the following molecular formula? N₄O₁₀.

N₂O₅

Molecular Formulas

100

This is the difference between molecular formula and empirical formula.

What is empirical formula shows ratio of atoms while molecular formula shows the number of each atom in 1 molecule? (subscripts are different)

200

What is the molecular formula of a compound if its empirical formula is C₂OH₄ and it has a molar mass of 88 g/mol?

C₄O₂H₈

300

The empirical formula of the anticancer drug altretamine is C₃H₆N₂. The experimental molar mass is 210 g/mol. What is the molecular formula?

C₉H₁₈N₆.

400

What is the molecular formula for a compound that is 16.4% H and 83.6% C and has a mass of 172.4g/mol.

C₁₂H₂₈?

500

This is the molecular formula of a compound that has an empirical formula of C₅H₁₂N₂ and a molar mass of 300 g/mol.

What is C₁₅H₃₆N₆?

Unit Conversions

100

How many moles do you have in 98.5 grams of gold?

0.5 moles

200

This is the mass of 6.39 moles of NaCl

373.8 grams

300

This is how many molecules are in 25 g of NH₃

  8.86 x10²³ molecules 

400

This is how many atoms are in 100g of KOH

3.22 x 10²⁴ atoms

500

What is the volume of 4.148 moles of fluorine gas.

98.9 liters

Percent composition

100

Calculate the mass percentage of H in HCl.

2.77%

200

calculate the mass percent of of each element in NH₄.

N: 77.8% H: 22.2%

300

What is the percent by mass of carbon in the compound C₂H₄

85.6%

400

What is the mass percent of Hydrogen in penicillin C₁₄H₂₀N₂SO₄?

6.453%

500

Determine the percentage of composition (by mass) of each element in the following compound: H₂SO₄

H= 2.06%

S=32.69%

O=65.25%