1 atomic structure

Question 1

define isotopes

Answer 1

atoms of the same element which have the same number of protons but different number of neutrons

Question 2

describe and explain the trend of atomic radius across a period

Answer 2

it decrease across a period, due to increased number of protons, shielding effect does not change significantly

Question 3

describe and explain the trend of atomic radius down a group

Answer 3

it increases down a group, due to the increased number shell of electrons

Question 4

shape of s orbitals

Answer 4

spherical shape

Question 5

shape of p orbitals

Answer 5

dumbbell shape

Question 6

free radical

Answer 6

a species with one or more unpaired electrons

Question 7

define the term first ionisation energy

Answer 7

the energy required to remove one mole of electrons from one mole of gaseous atoms of an element to form one mole of gaseous 1+ ion

Question 8

describe and explain the trend of ionisation energy across a period

Answer 8

it increases across a period. shielding effect stays constant, the number of protons increase which leads to a increase of effective nuclear charge

Question 9

describe and explain the trend of ionisation energy down a group

Answer 9

it decreases down a group. the distance between the nucleus and the outer electrons increases, the increased shielding effect due tot he increased number of shells of electrons

Question 10

factors affecting ionisation energy

Answer 10

• size of nuclear charge
• distance between the nucleus and valence electrons
• shielding effect of inner electrons
• spin pair repulsion