Bonding and properties- Unit 2 Flashcards
Why do metals conduct electricity?
They have free electrons can move throughout
the metal
carry an electrical charge
Why do ionic substances only conduct electricity
when it is molten or dissolved?
When solid the ions can’t move when melted or
dissolved
ions are free to carry an electrical charge
Why does graphite conduct electricity?
Each carbon gives 3 electrons to covalent bond
spare electron is delocalised
so it can carry an electrical charge
Why is the melting point of ionic substances high?
Strong electrostatic forces of attraction between
oppositely charged ions
which take a lot to energy to break
Why is the melting and
boiling point of simple
covalent low?
Weak intermolecular bonds
between molecules
which take little energy
to break
Why is the melting and
boiling point of diamond
so high?
4 strong covalent bonds
between carbons
take a lot of energy
to break
What is a metallic bond?
Strong electrostatic attraction between positive metal ions and a sea of delocalise electrons
What are the properties
of graphite- relate it
to it’s structure
Slippery- layers
Conducts- free electron
High MP- 3 strong covalent
bonds per carbon
What is the bonding between: 1)Non metals 2) Metal and non metal 3) metals
1) Covalent
2) Ionic
3) Metallic
Why do things melt?
Particles vibrate enough
to overcome
intermolecular bonding
What do
you get when an
atom
gains/loses an electrons?
An ion
Gain electron Negative
Lose electron Poitive
What is an ionic bond?
The electrostatic attraction
between 2 oppositely charged ion
What is a covalent bond?
Shared
Paired of electrons
between two non-metals
What is a metallic bond?
Electrostatic attraction
between positive metal ions
and a sea of de-localised electrons
Why is an alloy stronger than pure metal?
Irregular shape
due to different sized atoms
hard to slide over each other
