Bonding Flashcards
Which group rarely form bonds
The noble gases
How many types of bonding are there
3
What groups do ionic bonds occur between
Metals and non-metals
Electronegativity
The power/tendency of an atom to attract the electron density/ bonding pair in a covalent bond towards itself
First ionisation energy
The amount of energy required to remove one mole of electrons from one mole of gaseous atoms forming one mole of gaseous 1+ atoms
What groups do covalent bonds occur between
Non-metals only
How do ionic bonds work
One or more electron is stolen from the outer shell of the metal and then transferred over to the non-metal
Why does ionic bonding occur
So the electron orbitals can become as close to a noble gas as possible
What force attracts the ions together
Electrostatic forces
What structure do ions take up
Ionic lattices
Why are ionic lattices solid at room temperature
They are in a giant ionic lattice and thus have strong attraction in the lattice
Why are ionic substances brittle
They are alternating patterns of ions in a lattice shape. They shatter because they are unable to move past each other
What happens to the electrons in a covalent bond
They are shared between the atoms
Do covalent bonds carry charge
No as they are shared electrons and not transferred
How are covalent bonds held together
They are held together by electrostatic attraction between the nuclei and the shared electrons
What is the difference between a double and single covalent bond
In single 1 pair of electrons are shared
In double 2 pairs of electrons are shared
What is it called when a covalent molecule accepts another atom
Co-ordinate/dative bonds
What does metallic bonding occur between
Metal atoms
What happens to the electrons in a metallic bonding
They become delocalised
Which bonds are usually broken first
The weakest bond (the lowest bond enthalpy)
What affects the electronegativity
Nuclear charge
Distance between electron and outer shell
Atomic shielding
In relation to electronegativity, the smaller the atom,….
The closer the nucleus is to the outer electrons and is more electronegative
In relation to electronegativity
The larger the nuclear charge for a given shielding effect …
The greater the electronegativity
What is a polar bond
It is the unequal sharing of the electron between atoms that are covalently bonded
What happens to polarity when 2 identical atoms bond
They form a non-polar bond
What happens when 2 different atoms covalently bond
The electrons will be pulled towards the more electronegative atom
How is polarity represented
δ- or δ+
What is the weakest intermolecular force
Van der waals forces
What is the average strength intermolecular force
Dipole-dipole force
What is the strongest intermolecular force
Hydrogen bonding
How do dipoles work in molecules
Dipoles can cancel if it is mirrored eg linear molecules
Dipole- dipole forces act on what
They act on molecules with permanent dipoles
How do van der waals forces work
It’s electrostatic attraction between the temporary dipoles caused by the electron “orbits”
What do van der waals forces act on
All atoms or molecules at all times
What affects the probability of van der waals forces
Having more electrons
What is hydrogen bonding
When a hydrogen atom gets “sandwiched” between 2 very electronegative atoms forming a strong bond
What are the conditions required for hydrogen bonding
A hydrogen atom that is bonded to a very electronegative atom forcing it to be partly positive
A very electronegative atom with lone pairs
What are the atoms able to form hydrogen bonds
Oxygen,nitrogen,fluorine
