2.2.2 - Bonding and structure
No description yet. This curated deck is ready for daily study.
Card preview (24)
What are the 3 main types of chemical bonds?
Ionic Covalent Metallic
Define ionic bonding
The electrostatic attraction between positive and negative ions
Give an example of a ionically bonded structure
NaCl (Sodium chloride)
Define covalent bonding
Electrostatic attraction between a shared par of electrons and the nuclei
Define metallic bonding
Electrostatic attraction between the positive metal ions and the sea of delocalised electrons
Electrons in which shell are represented in a dot and cross diagram?
The outer shell
Why does giant ionic lattices conduct electricity when liquid but not when solid?
In solid state, the ions are in fixed positions and thus cannot move. When they are in liquid state, the ions are mobile and thus can freely carry the charge
Giant ionic lattice have high or low melting points? Explain your answer
They have high melting and boiling point because a large amount of energy is required to overcome the electrostatic bonds
In what type of solvents do ionic lattices dissolve?
Polar solvents e.g. water
Why are ionic compounds soluble in water?
Water has a polar bond. Hydrogen atoms have a positive charge and oxygen have a negative charge These charges are able to attract charged ions
What is it called when atoms are bonded by a single pair of shared electrons?
Single bond
How many covalent bonds does carbon form?
4
How many covalent bonds does oxygen form?
2
What is a lone pair?
Electrons in the outer shell that are not involved in the bonding
What is formed when atoms share two pairs of electrons?
double bond
What is formed when atoms share three pairs of electrons?
triple bond
What is average bond enthalpy
Measures of average energy needed to break the bond
What is a dative covalent bond?
A bond where both of the shared electrons are supplied by one atom
How are oxonium ions formed?
Formed when acid is added to water, H3O+
What does expansion of the octet mean?
When a bonded atom has more than 8 electrons in the outer shell
What are the types of covalent structures?
simple molecular lattice giant covalent lattice `
Describe the bonding in simple molecular structures
Atoms within the same molecule are held by strong covalent bonds and different molecules are held by weak intermolecular forces
Why do simple molecular structures have low melting and boiling point?
small amount of energy is enough to overcome the intermolecular forces
Can simple molecular structures conduct electricity?
No, they are non- conductors