bonding Flashcards
What is the max number of electrons in the 1st shell, 2nd shell & 3rd shell.
2,8,8
Define an ion?
Atom that has lost or gained electrons to become stable, they have either a positive or negative charge.
Atoms that lose electrons have a… charge and are called…
Atoms that gain electrons have a… charge and are called…
positive, cations
negative, anions
Magnesium + oxygen =
Magnesium oxide
Sodium + chlorine =
Sodium chloride
Nickel + sulphur + oxygen =
Nickel sulphate
Magnesium + nitrogen + oxygen =
Magnesium nitrate
What are features of ionic substances?
- giant lattice structure
- high melting & boiling point due to strong electrostatic forces between ions so a lot of energy is needed to break
What is covalent bonding?
Non metal atoms share electrons with other non metal atoms to obtain a full outer shell of electrons, when they share bonds they from covalent bonds.
What are the properties of molecular solids?
- low melting and boiling points
- usually soft and break easily
- insoluble in water
- cannot conduct electricity
What’s the structure of diamond?
- giant lattice structure
- each atom is covalently bonded to 4 others
- cannot conduct electricity (no delocalised electrons)
- high melting & boiling point (lot of energy needed to break the bonds)
- very hard
What’s the structure of graphite?
- giant lattice structure
- each atom covalently bonded to 3 others
- can conduct electricity (delocalised electron)
- high melting and boiling point (lot of energy needed to break bonds)
- soft
What are the properties of metals?
- solid at room temp
- high density
- shiny
- good conductor of electricity & heat
- high melting point
- malleable & ductile
Why are the properties of non metals?
- different states at room temp
- low density
- poor conductor of electricity & heat
- low melting points
- brittle
