Unit 6

Question 1

What is the Mole? Another name for the Mole?

Answer 1

Avogadro. A unit of measurement. The mole is always equal to 6.22 x 10^23 atoms. Allows us to use the unit of the gram.

Question 2

How to calculate Molar Mass? (The Mass of 1 Mole of any compound)

Answer 2

1. Find the correct formula (nomenclature unit)
2. Add up the mass pf all the atoms.
3. Remember SIG FIGS.

Question 3

Percent composition

Answer 3

A way of determining BY MASS, how much of each element is present in a compound.

Question 4

How to find percent composition?

Answer 4

1. Add up molar mass.
2. Find the total mass of each atom in the molecule.
3. Divide each atom by the total and multiply by 100. (To get the percentage)

Question 5

Conversion factor

Answer 5

A fraction (that always equals each other) that allows you to convert between units of matter.

Question 6

Converting grams and moles

Answer 6

1. Plug in what you know
2. Find the molar mass
3. Solve using SUS
4. SIG FIGS

Question 7

How many molecules are in 1 mole?

Answer 7

Avogadro’s number
6.022 x 10^23

Question 8

How many liters in 1 mole?

Answer 8

22.7 Liters but only at STP.

Question 9

STP

Answer 9

Standard temperature and pressure
Temp: 0C
Pressure: 1 atm

Question 10

Empirical Formulas

Answer 10

Simplified formulas (by the common denominator)

Question 11

How to calculate the empirical formula given percent composition?

Answer 11

1. Pretend the % are grams.
2. Convert grams to moles.
3. Divide all moles by the smallest mole.
4. Multiply to get a whole number.

Question 12

Molecular Formulas

Answer 12

The ACTUAL formulas of the compound. You can calculate this using the empirical formula.

Question 13

How to calculate the molecular formula given empirical formula?

Answer 13

1. Find the molar mass of the empirical formula.
2. Divide the molar mass of the molecular formula by the molar mass of the empirical formula.
3. Multiply the empirical formula by the answer of the division to get the molecular formula.