C8 - Periodicity

Question 1

Atoms order in the periodic table is determined by

Answer 1

Proton number

Question 2

How does atomic radius change across period 3

Answer 2

Decreases

Because electrons highest energy level is the same but nuclear charge becomes stronger

Question 3

How does melting point change from Na to Si

Answer 3

Small increases from Na to Al due to higher nuclear charge and more electrons.

Stronger electrostatic forces of attraction

Si is a macromolecular structure so it has the highest melting point

Question 4

How does melting point change from P to Cl2

Answer 4

S8 > p4 > cl2

Question 5

Why does melting point change from P to Cl2

Answer 5

S8 >p4>cl2 in terms of atoms

More atoms means more electrons so stronger van Der waals forces

Question 6

Which element has the lowest and highest melting point in period 3

Answer 6

Lowest - Argon
Highest - Silicon

Question 7

How does first ionisation energy change across period 3

Answer 7

Increases due to higher nuclear charge and lower atomic radius.