Ionic Bonding Flashcards
What is an ion?
The name giving to a resulting particle when an atom gains or loses electrons to give them a full outer shell.
What happens in ionic bonding?
Metal atoms transfer electrons to the non-metal atom (instead of sharing them like in covalent bonding)
What happens when metal ions lose electrons?
They become positive ions
What happens when metal ions gain electrons?
They become negative ions
How do ionic lattice structures work?
The ions have strong electrostatic forces of attraction which work in all directions -> therefore billions of ions can be bonded together in a 3D structure
How do you work out the formula of an ionic substance?
- From its bonding diagram (e.g: if there’s 2 fluoride ions for every magnesium, the formula would be MgF₂)
- From a lattice diagram (e.g: if there are 9 Fe²⁺ ions and 18 S⁻ ions the ratio is 9Fe²⁺18S⁻ which simplifies to FeS₂)
Name properties of ionic substances.
- High melting and boiling points
- Solids do not conduct electricity
- When melted or dissolved in water, they do conduct electricity
Why do ionic substances not conduct electricity when solid?
The ions are fixed in position so are not free to carry a charge
Why do ionic substances conduct electricity when melted or dissolved in water?
The ions are free to move and carry a charge
Why do ionic substances have high melting and boiling points?
The electrostatic force of attraction (between oppositely-charged ions) is strong and so requires lots of energy to break
Why are pure metals malleable?
Layers can slide over each other
Why do metals have high melting and boiling points?
Because the electrostatic force of attraction (between metal ions and delocalised electrons) is strong so requires a lot of energy to break it.
What is an alloy?
An alloy is a mixture of two or more metals or a metal with a non-metal. They are harder than pure metals.
Why are alloys less malleable than pure metals?
- Atoms of a different element are added to a pure metal
- The new atoms are a different size to the pure metal’s
- This disturbs the regular arrangements of the layers, so they can’t slide over each other
What charge would an ion of an element from group 1 form?
1+
What charge would an ion of an element from group 6 form?
2-
