periodicity onwards

Question 1

Define first ionisation energy

Answer 1

Amount of energy required to remove one mole of electrons from one mole of gaseous atoms to get one mole of gaseous 1+ ions

Question 2

Describe general trend of first ionisation energy down a group

Answer 2

decrease

Question 3

Describe general trend of first ionisation energy across a period

Answer 3

increase

Question 4

Factors that affect ionisation energy?

Answer 4

Nuclear attraction, nuclear charge ,shielding, atomic radius

Question 5

Why does ionisation energy decrease down a group

Answer 5

More shielding due to more shells, higher atomic radius, and this outweighs the greater nuclear charge. All this decreases nuclear attraction so less energy is required to ionise

Question 6

Why does ionisation energy increase across a period

Answer 6

Atomic radius decreases as more protons are added while the number of shells remains the same, Nuclear charge pulls the electrons inward. Increases attraction. Shielding is similar. So nuclear attraction is higher. So more energy required to ionise

Question 7

Complete the sentence: Halogens are in the (???) block of the periodic table

Answer 7

p

Question 8

Why is the first ionisation energy decrease from N -> O and P -> S, even though its supposed to go up?

Answer 8

Electrons start to pair up within their orbitals, which repel each other slightly, so less energy is required to ionise

Question 9

Define orbital

Answer 9

A region around nucleus capable of holding up to 2 electrons with opposite spins.

Question 10

Why does first ionisation energy decrease from Be –> B

Answer 10

p orbital energy > s orbital energy.

Question 11

What’s the trend in successive ionisation energies

Answer 11

increase within the same shell [less repulsion, and ion is becoming increasingly more positive], large increase between shells [decrease in atomic radius]

Question 12

What’s the equation for first ionisation energy for element X

Answer 12

X(g) –> X+(g) + e-

Question 13

What is metallic bonding?

Answer 13

strong electrostatic attraction between cations (positive ions) and delocalised electrons

Question 14

What is a giant metallic structure

Answer 14

the regular arrangement of positive ions surrounded by a sea of delocalised electrons.

Question 15

Why can graphene conduct electricity

Answer 15

Each carbon atom is bonded to 3 others so there is a delocalised electron free to move and carry the current

Question 16

Why is graphene so insoluble

Answer 16

Very Strong covalent Bonds

Question 17

2Mg + O2 –>

Answer 17

–> 2MgO

Question 18

2Ca + 2H2O –>

Answer 18

2Ca(OH)2 + H2

Question 19

What is Ca(OH)2 used for in agriculture

Answer 19

Neutralising acid soils