L2 - Chemistry - Atomic Structure

Question 1

What is a molecule?

Answer 1

• More than one atom bonded together
• can be the same type of atom or can be different atoms

Question 2

What is a compound?

Answer 2

• Combinations of different types of atom
• Pure substance
• Contains two or more elements chemicals combined

Question 3

What is an atom?

Answer 3

Smallest part of an element that can exist chemically But atoms are not the smallest particles

Question 4

What is the atomic number?

Answer 4

proton number

Question 5

What is the relative atomic mass (RAM)?

Answer 5

Sum of number of protons and number of neutrons

Question 6

What are isotopes?

Answer 6

Atoms of the same element with different numbers of neutrons

Question 7

Ratio of isotopes in chlorine gas

Answer 7

3:1
35:37

Question 8

How are electrons arranged ?

Answer 8

Arranged in successive principal energy levels (shells)
Given principle quantum numbers (n)

Question 9

Maximum electrons in first 3 shells

Answer 9

n=1 maximum 2 electrons
n=2 maximum 8
n=3 maximum 18 electrons

Question 10

Subshells and number electrons (up to n=4)

Answer 10

1
2 electrons
1s

2
8 electrons
2s, 2p

3
18 electrons
3s, 3p, 3d

4
32 electrons
4s, 4p, 4d, 4f

Question 11

How are atomic orbitals arranged?

Answer 11

• each orbital can hold a ,maximum of 2 electrons
• an atomic orbital is a region around an atom where there is a high probability of finding (a pair of) electrons
• atomic orbitals have direction

Question 12

Characteristics of S orbitals

Answer 12

• Spherical
• Symmetrical about all 3 axis
• Found at all quantum numbers
• Holds max 2 electrons

Question 13

Characteristics of P orbitals

Answer 13

• Dumbbell shape
• Identical in shape
• Point in different directions, one along each axis
• 3 p orbitals
• Found at n=2 and above
• Each orbital holds max 2 electrons

Question 14

Characteristics of D orbitals

Answer 14

• Complicated shape
• Five D orbitals
• Found at n=3 and above
• Each orbital holds max 2 electrons

Question 15

Characteristics of F orbitals

Answer 15

• Very complicated shape
• Seven F orbitals
• Found at n=4 and above
• Each orbital holds max 2 electrons

Question 16

How are electrons weird?

Answer 16

Exhibit wave particle duality

Question 17

What does it mean that the 5 3d orbitals are degenerate?

Answer 17

All have the same energy

Question 18

Why is the periodic table arranged in blocks?

Answer 18

Each block named for the orbital in which the “last” electron resides

Question 19

Electronic configuration - The Pauli exclusion principle

Answer 19

• Each orbital contains a maximum of two electrons
• Spins must be paired (antiparallel spin) for this to happen

Question 20

Electronic configuration - The Aufbau principle

Answer 20

• Electrons occupy the lowest vacant orbital

Question 21

Electronic configuration - Hund’s rule of maximum multiplicity