Chapter 5 Electrons and Bonding Flashcards
What is a shell
A shell is an energy level, comprised of sub shells called s p d f. The shell number is called the principal quantum number ‘n’
What is an Atomic Orbital
A region around the nucleus that can hold up to two electrons with opposite spins
What shape are s orbitals
The electron cloud is within the shape of a sphere
As the shell number ‘n’ increases, what happens to the radius of its s-orbital
It increases
What shape are p orbitals
Dumb-bell
There 3 orbitals at right angles to eachother
How many electrons can fit in s orbitals
2
How many electrons can fit in p orbitals
6
How many electrons can fit in d orbitals
10
How many electrons can fit in f orbitals
14
How many electrons can fit inside shell n=1
2
How many electrons can fit in shell n=2
8
How many electrons can fit in shell n=3
18
How many electrons can fit in shell n=4
32
What is the electron configuration
From 1s to 4f
1s 2s 2p 3s 3p 4s 3d 4p 4d 4f
What is the electron configuration
From 1s to 4f with the number of electrons in each sub-shell
1s²
2s²
2p⁶
3s²
3p⁶
4s²
3d¹⁰
4p⁶
4d¹⁰
4f¹⁴
How many s-orbitals are there in each shell from n = 1 onwards
1
How many p-orbitals are there in each shell from n = 2 onwards
3
When overlaped on to 1 diagram, why do the 3, p orbitals extend out further than the nucleus
They have a slightly higher energy
How many d-orbitals are there in each shell from n = 3 onwards
5
How many f-orbitals are there in each shell from n = 4 onwards
7
Which sub-shells are present in shell n = 1
1s
Which sub-shells are present in shell n = 2
2s + 2p
Which sub-shells are present in shell n = 3
3s + 3p + 3d
Which sub-shells are present in shell n = 4
4s + 4p + 4d + 4f
True or false:
4s fills before 3d
True
How would 2 electrons be represented in an orbital
Box diagram
|↑↓|
How are orbitals filled
Each orbital of the same energy is occupied before spin pairing occurs in the orbitals with 2 electrons paired together
Which of these has been drawn correctly
- |↑↓| |↑↓| | |
- |↑↓| |↑ | |↑ |
2 - |↑↓| |↑ | |↑ |
Write the electron configuration of Magnesium z=12
1s²2s²2p⁶3s²
How do you write the shorthand electron configuration
Find the previous noble gas and write the remaining electron configuration
Write the electron configuration of Potassium Z=19
1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Write the electron configuration of Scandium Z=21
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s²
Which sub-shell is filled first 4s or 3d
4s
What two elements have an exemption to the rule of electron configuration
Chromium & Copper
What is the electron configuration of Chromium
An exemption
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹
What is the electron configuration of Copper
An exemption
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹
If this is the electron configuration of an Mg atom, write the electron configuration of an Mg²⁺ ion
1s² 2s² 2p⁶ 3s²
1s² 2s² 2p⁶
If this is the electron configuration of a Cl atom, write the electron configuration of a Cl⁻ ion
1s² 2s² 2p⁶ 3s² 3p⁵
1s² 2s² 2p⁶ 3s² 3p⁶
Which sub-shell loses electrons first when forming electron configurations of Ions:
4s or 3d
4s
If this is the electron configuration of an Fe ion, write the electron configuration of an Fe²⁺ ion
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶ 4s²
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶
If this is the electron configuration of an Fe ion, write the electron configuration of an Fe³⁺ ion
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶ 4s²
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵
What is Ionic bonding
The electrostatic attraction between positive ions (cations) and negative ions (anions)
Give examples of common cations
- Metal ions
- K⁺
- Ca²⁺
- Mg²⁺
- Al³⁺ - Ammonium ion
- NH₄⁺
Give examples of common anions
- Non-metal ions
- Cl⁻
- O²⁻
- S²⁻
- Polyatomic ions
- SO₄²⁻
- CO₃²⁻
- NO₃⁻
What is the structure of ionic compounds
- Oppositely charged ions attract each other strongly
- Each ion attracts oppositely charged ions in all directions
- In the solid state, the ions build up into a giant ionic lattice
- Ions are closely packed in a regular lattice arrangement
Describe the arrangement of ions in the ionic lattice of Sodium Chloride
- Regular cubic arrangement of Na⁺ and Cl⁻ ions
- Each Na⁺ ion is surrounded by 6 Cl⁻ ions
- Each Cl⁻ ion is surrounded by 6 Na⁺ ions
What are the properties of ionic compounds
- Solid at room temperature
- High melting and boiling points
- Tend to dissolve in polar solvents such as water
- Conduct electricity only when molten or in aqueous solution (not when solid
Why are ionic compounds solid at room temperature
At room temperature there isn’t energy to overcome electrostatic attractive forces between cations and anions in the giant ionic lattice
Why do ionic compounds have high melting and boiling points
- Large electrostatic attractive forces between cations and anions in the giant ionic lattice
- High temperatures are needed to provide the energy required to overcome these forces
- Therefore most ionic compounds have high melting and boiling points
What 2 factors affect melting and boiling point of ions
- Ionic charges
- Size of ions
How does the ionic charge affect the strength of the bond
The strength of the ionic bond increases when the charge on the ions increases
How does the sixe of the ions affect the strength of the bond
The strength of the ionic bond increases when the size of the ions decreases
Do ionic compounds tend to dissolve in polar solvents such as water
Yes
Can ionic compounds conduct electricity in solid state
No
Why can’t ionic compounds conduct electricity in solid state
- Ions held in fixed positions in giant ionic lattice
- No mobile charge carriers
- No electrical conductivity
Why can ionic compounds conduct electricity in liquid or aqueous state
- Ions are free to move
- Ions are mobile charge carriers
- Electricity is conducted
What is an element
A substance made up of only one type of atom
What is a compound
A substance consisting of two or more elements chemically bonded together
What is a molecule
A group of atoms covalently bonded together
What is covalent bonding
Covalent bonding is the strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
Where can covalent bonding occur
- Non metalic elements
- Compounds of non-metalic elements
- Polyatomic ions
What is a covalent bond
the overlap of atomic orbitals, each containing one electron, to give a shared pair of electrons
Show the displayed formula of a hydrogen molecule
H — H
Is a covalent bond localised
Yes
Where is a covalent bond localised
The electrostatic attraction is localised and is solely between the shared pair of electrons in the covalent bond and the nuclei of the bonding atoms
True or False:
An ion attracts oppositely charged ions in all directions resulting in a giant ionic lattice
True
What is a shared pair of electrons called
A shared pair of electrons is called a bonded pair of electron
What is a pair of non-bonding electrons called
A pair of non-bonding electrons is called a lone pair of electrons
How many covalent bonds can an atom of each element form:
Hydrogen
Oxygen
Nitrogen
Carbon
HONC
Hydrogen - 1
Oxygen - 2
Nitrogen - 3
Carbon - 4
When can an expansion of the octet occur
From n=3 when a d-sub-shell becomes available
What is a double covalent bond
The electrostatic attraction is between two shared pairs of electrons and the nuclei of the bonding atoms
What is a triple covalent bond
The electrostatic attraction is between three shared pairs of electrons and the nuclei of the bonding atoms
What is a dative covalent bond
A shared pair of electrons in which the bonded pair has been provided by one of the bonding atoms only. Shown as an arrow, with the arrow pointing away from the atom that contributes both electrons
Give an example of an ion containing dative covalent bonds
NH₄⁺
