Atomic structure 2

Question 1

define the term ionisation energy

Answer 1

ionisation energy is the amount of energy required to remove one mole of electrons from one mole of gaseous atoms of an element to form one mole of gaseous ions

Question 2

what are the standard conditions for ionisation energies to be measured under

Answer 2

298K ad 101kPa

Question 3

write an example of the first and second ionisation energy of an element of your choice

Answer 3

check internet to see if correct

Question 4

what is the trend of ionisaation energy across a period and down a group

Answer 4

first ionisation energy increas across a period and decreasse down a group

Question 5

what are the four factors affecting size of the first ionisation energy

Answer 5

• size of nuclear charge
• distance of outer elecetrons from nucleus
• shielding effect of inner electrons
• spin pair electrons

Question 6

explain how I.E increases across a period with reference to the 4 factors

Answer 6

-across a period nuclear charge increases causing atomic radius to decrease as the outershell is being pulled closer to the nucleus therefore the distance between the nucleus ad outershell eectrons decreases making it harder to remove an electron as you move across a period. shielding remains reasonably constant

Question 7

explain how I.E decreases down a group

Answer 7

-down a group nuclear charge decreases causing atomic radius to increase. as atomi radius increase the distance between outershell and the nucleus increases which decreases the pull of outershell electrons to the nucleus making it easy to remove an electron as yu go down the group. shielding effect increases as there are more electrons

Question 8

state what happens to nuclear charge, shielding effect, distance between nucleus and outershell electrons, number of shells and atomic/ionic radius when ionisation energies increase and decrease

Answer 8

across a period:

• nuclear charge increases
• atomic radius decreases
• shielding is constant
• number of shells remains the same
• distance of outer shell electrons and nucleus decreases

down a group:

• nuclear charge decreases
• atomic radius increases
• shielding increases
• number of shells increases and distance of outershell electrons and nucleus increases

Question 9

explain how size of nuclear charge affects IE

Answer 9

-nuclear charge increases with increasing atomic number meaning there are greater forces of attraction between nucleus and electrons hence more energy required to overcome forces

Question 10

explain how distance of outershell electrons from nucleus affects IE

Answer 10

electrons in shells farther away from the nucleus are less attracted to it so nuclear attraction is weaker so the further the outershell electron the weaker the attractive forces from the nucleaus lowering the inoisation energy

Question 11

explain how shielding effect of inner electrons affects ionisation energy

Answer 11

shielding effecte is whe the electrons in full inner shells repel electrons iin outer shells preventing them from feeling the full nuclear charge so the more shells an atom has the greater the shielding effect lowering ionisation energy

Question 12

explain how spin pair repulsion affects IE

Answer 12

electrons in the same atomic orbital in a subshell repel more than than electrons in different orbitals making it easier to remove an electron