(Wk2) Electron shells, Molecular Formula, Chemical amounts and Concentrations

Question 1

What are the inner and outer electrons in an atom called?

Answer 1

-Inner: Core
-Outer: Valence

Question 2

Which electrons are involved in the forming of chemical bonds with other atoms?

Answer 2

The valence (outer) electrons.

Question 3

Who developed the Bohr model of the atom?

Answer 3

Niels Bohr- he proposed that electrons each orbit the nucleus at a particular distance, implying that they occupy fixed shells.

Question 4

What are the 4 different types of orbitals?

Answer 4

s, p, d, f

Question 5

How many orbitals can the shells occupy?

Answer 5

s: 1
p: 3
d: 5
f: 7

Question 6

What are the maximum number of electrons each orbital can hold up?

Answer 6

2

Question 7

What is valency?

Answer 7

Valency is how many electrons need to be gained or lost to become stable charged ions with full valence electron shells.

Question 8

How many atoms are in a mole?

Answer 8

6.023 x 10^23 atoms. This is known as the avogadro’s constant.

Question 9

What is Concentration and what are the units of Concentration?

Answer 9

Concentration is the amount of a substance in a particular volume. Units are mol L^-1 or M.

Question 10

Formula to work out Concentration?

Answer 10

Concentration = amount of solute / volume of solution

Question 11

Formula to work out Moles?

Answer 11

Moles (mol) = mass (g) / Molar mass (g mol^-1)