Physical Properties of Elements

Question 1

What happens to atomic radius going across the period left to right?

Answer 1

It decreases because, when going across the group, more protons and electrons are added. However, the extra electrons are added to the same s and p sub-shells, so the size does
not increase. The extra protons increase the nuclear charge. The increased nuclear charge attracts the extra electrons and pulls them closer to the nucleus. This leads to a decrease in atomic radius.

Question 2

What happens to the atomic radii as you go down a group?

Answer 2

It increases because the extra electrons are added to additional shells, and so the radius increases. Although the nuclear charge increases, the number of inner shells increases, and so the nuclear charge is shielded more. This means that the atomic
radius increases.

Question 3

What is meant by Isoelectronic?

Answer 3

Having the same numbers of electrons

Question 4

What are Cations?

Answer 4

Ions with a positive charge

Question 5

What are Anions?

Answer 5

Ions with a negative charge

Question 6

What does Electronegativity depend on?

Answer 6

 the number of protons in the nucleus
 the distance from the nucleus of the bonding pair of electrons
 how much shielding there is from inner electrons

Question 7

Most electronegative element

Answer 7

Fluorine

Question 8

What is meant by electronegativity?

Answer 8

A measure of the tendency of an atom to attract a bonding pair of electrons. It increases as you go across a period. It decreases as you go down a group.

Question 9

What is meant by First ionisation energy?

Answer 9

The energy needed for one mole of electrons to be removed from one gaseous atoms

Question 10

What is meant by Electron affinity?

Answer 10

The charge in energy when one mole of a gaseous atom gains one mole of electrons to form a negative ion

Question 11

What is meant by Periodicity?

Answer 11

the repeating pattern is seen in the
elements in the periodic table

Question 12

What is meant by malleable?

Answer 12

Can be hammered into shape with breaking

Question 13

What is meant by ductile?

Answer 13

Can be hammered or stretched into wires without breaking

Question 14

How does metallic bonding allow a solid or liquid metal to electrically conduct?

Answer 14

The delocalised electrons in metals also absorb heat energy, which gives them kinetic energy. This energy is then transferred through the metal by these electrons. Metals are good thermal conductors

Question 15

What happens to the melting and boiling point going down group 1?

Answer 15

The melting and boiling points decrease. This means that the forces of attraction get weaker

Question 16

What happens to the melting and boiling point when you go down group 7?

Answer 16

The melting and boiling points increase, meaning that the forces of attraction are getting stronger