Chapter 3 Chemistry Fundamentals

Question 1

What are the six bae units of SI?

Answer 1

1. meter
2. kilogram
3. second
4. mole
5. Kelvin
6. Ampere

Question 2

What is an angstrom?

Answer 2

1 A = 10^(-10) m

Question 3

What is density (formula, SI unit, common unit)

Answer 3

• density = mass/volume
• SI unit = kg/m^3
• common unit = g/cm^3

Question 4

What is a molecular formula?

Answer 4

Something that identifies the type and number of atoms in a molecule (covalently bonded atoms)

Question 5

What is an empirical formula?

Answer 5

A formula that gives the smallest whole number ratio of atoms present in a molecule.

Question 6

What is formula weight?
What is molecular weight?

Answer 6

• Formula weight - in amu; sum of atomic masses of all atoms in a compound
• Molecular weight - in grams; magnitude is equivalent to formula weight

Question 7

What is a mole?

Answer 7

It is a term used to denote 6.022e23 (Avogadro’s number) entities.

Question 8

What is a mole in the periodic table?

Answer 8

1 mole of any atom is the magnitude of its atomic mass in grams.
For example, 1 atom C = 12 amu
=> 1 mole C = 12 g

Question 9

What does percent composition by mass look like?

Answer 9

% composition =
(mass of atom in molecule/total mass of molecule)*100%

Question 10

What is molarity?

Answer 10

Molarity (M) = moles of solute/volume of solution
- mol/L

Question 11

What is a limiting reagent?

Answer 11

It is the reactant that runs out first; it determines the amount of product formed

Question 12

What is an atom’s oxidation state?

Answer 12

The oxidation state shows the change in the ability to attract electrons when an atom forms a compound.

Question 13

How to assign electronegativity?

Answer 13

• Group 1 = +1
• Group 2 = +2
• H = +1 commonly, -1 with metals
• Halogens = -1
• Oxygen = -2, unless in a peroxide