Ionic bonding

Question 1

Ionic bonding

Answer 1

Strong electrostatic attraction between oppositely charged ions

Question 2

What is an ionic structure?

Answer 2

A Solid material consisting of a regular array of oppositely charged ions through a lattice structure

Question 3

How are ions arranged in a lattice?

Answer 3

In a way where the oppositely charged ions attraction is greater than the repulsion between similarly charged ions

Question 4

Do bond angles and the ions orientation matter in an ionic structure?

Answer 4

No because the electrostatic attraction is not directional therefore doesn’t effect the shape unlike covalent bonding

Question 5

Do the ionic bonds actually hold the shape together?

Answer 5

No but the total interactions ions have with each other which is the lattice energy is what does

Question 6

What are the charges like in an ionic compound?

Answer 6

They balance each other out exactly so overall charge is 0

Question 7

What affect the strength of an ionic bond?

Answer 7

The stronger the electrostatic attraction between oppositely charged ions which is affected by:
Ionic charges
Ionic radii

Question 8

Ionic charges affect on ionic bond strength

Answer 8

The greater the charge on an ion, the stronger the ionic bond
Therefore stronger melting/boiling points

Question 9

Ionic radii affect on ionic bond strength

Answer 9

Because electrostatic attraction gets weaker by distance:
Smaller ions with smaller radii are packed closer together thus have stronger ionic bonding
Therefore stronger melting/boiling points

Question 10

What does the size of an ion depend upon?

Answer 10

It’s number of electron shells and it’s atomic number

Question 11

Trend of ionic radii

Answer 11

-Increases going down a group
-Across a collection of isoelectronic ions, the radius decreases as atomic number increases

Question 12

Ionic radii down a group

Answer 12

Increases because going down the group the atomic number increases
Therefore increased number of electrons occupy extra electron shells

Question 13

What are isoelectronic radii?

Answer 13

Ions of different atoms but with the same number of electrons
because they lose or gain electrons to have a full outer shell

Question 14

Isoelectronic radii trend?

Answer 14

The number of electrons stay the same however proton number increases
So electrons are attracted to the nucleus more as you go across, decreasing radii because they are pulled in

Question 15

What structures does ionic bonding form

Answer 15

Giant ionic lattices

Question 16

Why do ionic structure form?

Answer 16

Because each ion is electrostatically attracted attracted in all directions to the ions of opposite charges eg can form a lattice because the ionic bonds forms between all ions

Question 17

Properties of ionic compounds

Answer 17

High melting point
Soluble in polar solvents, insoluble in non polar solvents
No conduction of electricity when solid but conduction when molten/ dissolved
Brittle

Question 18

Why do ionic compounds have high melting points?

Answer 18

Because the ions are held together by strong electrostatic attraction between oppositely charged ions which requires a lot of energy to overcome

Question 19

Why do ionic compounds dissolve in polar solvents?

Answer 19

Because the particles are charged thus are ions
Therefore the ions are pulled apart by polar molecules from a polar solvent

Question 20

Why do ionic compounds conduct electricity only when molten or dissolved?

Answer 20

Because as a solid, the ions are in a fixed position by strong ionic bonds and can’t carry a charge but when dissolved/ molten the charged particles (ions) are free to carry it

Question 21

Why are ionic compounds brittle?

Answer 21

If a force was applied to pull layers of ionic compound over each other, the similarly charged ions would repel each other. This repulsion is strong, causing ionic compounds to break when hammered (thus brittle)

Question 22

Migration of ions: copper ii chromate vi

Answer 22

When you electrolyse (electrolysis) copper ii chromate vi on wet filter paper the ions will move to the opposite charged electrode

Question 23

Which electrode does copper ii migrate to?

Answer 23

The cathode (negative electrode) because it’s a positive metal ion

Question 24

What colour is at the cathode?

Answer 24

Blue because the copper ii ions migrate there thus causes a blue colour

Question 25

What colour is copper ii ions?

Answer 25

Blue

Question 26

What electrode does chromate vi migrate to?

Answer 26

Anode because they are negative charged ions

Question 27

What colour is the anode?

Answer 27

Yellow because the chromate ions are discharged there which are yellow

Question 28

What colour are chromate ions?

Answer 28

Yellow

Question 29

What colour is copper ii chromate vi?

Answer 29

Green because it is a mixture of:
Copper ii ions = blue
Chromate vi ions = yellow