Periodicity

Question 1

trend in atomic radius across period 3

Answer 1

-decreases, even though there are still the same number of shells
-nuclear charge increases as number of protons increases
-causes increase in electrostatic forces of attraction

Question 2

why does shielding effect not increase across period 3

Answer 2

electrons are being added to the same outer shell

Question 3

trend in first ionisation energy across period 3

Answer 3

-increases
-nuclear charge increases
-electrostatic forces of attraction between nucleus and electrons increases

Question 4

trend in melting point across period 3

Answer 4

-increases
-in the metals it is due to more delocalised electrons per metal atoms
-atomic radius decreases

-silicon has a very high melting point as it has a giant covalent structure

Question 5

What are the different blocks of the periodic table and what determines it

Answer 5

S, P, D, F
-determined by electron orbitals