AQA A-Level Chemistry (new spec) 1.3
Bonding
Ionic Bonding - Correct Answers-The electrostatic force of attraction between two oppositely
charged ions formed by electron transfer
Covalent Bonding - Correct Answers-A shared pair of electrons
Dative Covalent Bonding (AKA Co-ordinate bonding) - Correct Answers-Formed when the
shared pair of electrons in the covalent bond come from only one of the bonding atoms.
Metallic Bonding - Correct Answers-The electrostatic force of attraction between the positive
metal cations and the sea of delocalised electrons
Factors affecting the strength of metallic bonding: The number of protons - Correct Answers-
The more protons in the cations, the stronger the electrostatic force of attraction between the
cations and the sea of delocalised electrons
Factors affecting the strength of metallic bonding: Number of delocalised electrons per atom -
Correct Answers-The more delocalised electrons, the stronger the electrostatic force of
attraction
Factors affecting the strength of metallic bonding: Size of ion - Correct Answers-The smaller the
ion, the stronger the electrostatic force of attraction
Electronegativity - Correct Answers-The relative tendency of an atom in a covalent bond in a
molecule to attract electrons in a covalent bond towards itself
Why does electronegativity increase as you go across a period? - Correct Answers--The number
of protons increased
-The atomic radius decreases because the electrons in the same shell are pulled in more
Why does electronegativity decrease as you go down a group? - Correct Answers--Distance
between the nucleus and the outer electrons increases
-Shielding increases
, Why aren't the noble gases electronegative? - Correct Answers-Because they don't form bonds
Using electronegativity to predict bonding: Covalent - Correct Answers-If both atoms have a
similar electronegativity, the pull on the electrons from them will be of a similar strength,
making a non-polar covalent bond.
If one atom has a stronger electronegativity than the other, the electrons will be pulled more
towards one atom, making the bond polar-covalent
Using electronegativity to predict bonding: Ionic - Correct Answers-If the electronegativity
difference is really large, the sharing of electrons is so uneven that the more electronegative
atom has full possession of the 2 electrons, creating an ionic bond
Using electronegativity to predict bonding: Metallic - Correct Answers-If both atoms have a low
electronegativity, neither can attract electrons, so the electrons don't remain localised to the
bond at all, causing a sea of delocalised electrons and a metallic bond
Orbitals & Covalent Bonds - Correct Answers-When a covalent bond is formed, the 2 outer
orbitals overlap, forming a normal covalent bond.
Some atoms promote electrons to give more unpaired electrons and to allow more covalent
bonding. For example, carbon promotes one of the electrons in the 2s orbital to the 2p orbital,
meaning there are 4 unpaired electrons, so it can form 4 covalent bonds
Orbitals and Dative Covalent Bonds - Correct Answers-Any atom with filled valence shell (outer
shell) orbitals can donate their electrons for the covalent bond. This includes group 5,6,7 and 0
Any atom which has an empty orbital in their valence shell can accept a pair of electrons.
Sigma Bonds - Correct Answers-Where the atomic orbitals overlap directly along the
internuclear axis. All single bonds are sigma bonds.
Pi Bonds - Correct Answers-Where the atomic orbitals overlap above and below the
internuclear axis. All double bonds contain a sigma and a pi bond. All triple bonds contain a
sigma bond and 2 pi bonds
Strength of covalent bonds is affected when.. - Correct Answers-The atoms are smaller because
the closer the electrons are to the nuclei, the stronger the bond
Molecular Shapes: 2 electron pairs - Correct Answers-Linear, 180 degrees
Molecular Shapes: 3 electron pairs - Correct Answers-Trigonal Planar, 120 degrees
Bonding
Ionic Bonding - Correct Answers-The electrostatic force of attraction between two oppositely
charged ions formed by electron transfer
Covalent Bonding - Correct Answers-A shared pair of electrons
Dative Covalent Bonding (AKA Co-ordinate bonding) - Correct Answers-Formed when the
shared pair of electrons in the covalent bond come from only one of the bonding atoms.
Metallic Bonding - Correct Answers-The electrostatic force of attraction between the positive
metal cations and the sea of delocalised electrons
Factors affecting the strength of metallic bonding: The number of protons - Correct Answers-
The more protons in the cations, the stronger the electrostatic force of attraction between the
cations and the sea of delocalised electrons
Factors affecting the strength of metallic bonding: Number of delocalised electrons per atom -
Correct Answers-The more delocalised electrons, the stronger the electrostatic force of
attraction
Factors affecting the strength of metallic bonding: Size of ion - Correct Answers-The smaller the
ion, the stronger the electrostatic force of attraction
Electronegativity - Correct Answers-The relative tendency of an atom in a covalent bond in a
molecule to attract electrons in a covalent bond towards itself
Why does electronegativity increase as you go across a period? - Correct Answers--The number
of protons increased
-The atomic radius decreases because the electrons in the same shell are pulled in more
Why does electronegativity decrease as you go down a group? - Correct Answers--Distance
between the nucleus and the outer electrons increases
-Shielding increases
, Why aren't the noble gases electronegative? - Correct Answers-Because they don't form bonds
Using electronegativity to predict bonding: Covalent - Correct Answers-If both atoms have a
similar electronegativity, the pull on the electrons from them will be of a similar strength,
making a non-polar covalent bond.
If one atom has a stronger electronegativity than the other, the electrons will be pulled more
towards one atom, making the bond polar-covalent
Using electronegativity to predict bonding: Ionic - Correct Answers-If the electronegativity
difference is really large, the sharing of electrons is so uneven that the more electronegative
atom has full possession of the 2 electrons, creating an ionic bond
Using electronegativity to predict bonding: Metallic - Correct Answers-If both atoms have a low
electronegativity, neither can attract electrons, so the electrons don't remain localised to the
bond at all, causing a sea of delocalised electrons and a metallic bond
Orbitals & Covalent Bonds - Correct Answers-When a covalent bond is formed, the 2 outer
orbitals overlap, forming a normal covalent bond.
Some atoms promote electrons to give more unpaired electrons and to allow more covalent
bonding. For example, carbon promotes one of the electrons in the 2s orbital to the 2p orbital,
meaning there are 4 unpaired electrons, so it can form 4 covalent bonds
Orbitals and Dative Covalent Bonds - Correct Answers-Any atom with filled valence shell (outer
shell) orbitals can donate their electrons for the covalent bond. This includes group 5,6,7 and 0
Any atom which has an empty orbital in their valence shell can accept a pair of electrons.
Sigma Bonds - Correct Answers-Where the atomic orbitals overlap directly along the
internuclear axis. All single bonds are sigma bonds.
Pi Bonds - Correct Answers-Where the atomic orbitals overlap above and below the
internuclear axis. All double bonds contain a sigma and a pi bond. All triple bonds contain a
sigma bond and 2 pi bonds
Strength of covalent bonds is affected when.. - Correct Answers-The atoms are smaller because
the closer the electrons are to the nuclei, the stronger the bond
Molecular Shapes: 2 electron pairs - Correct Answers-Linear, 180 degrees
Molecular Shapes: 3 electron pairs - Correct Answers-Trigonal Planar, 120 degrees