With reference to the variation of properties in the Periodic Table, which of the following is generally true?

1. Atomic size increases from left to right across a period.
2. Ionization potential increases from left to right across a period.
3. Electron affinity increases going down a group.
4. Electronegativity increases going down a group.

An element in period 3 whose electron affinity is zero is :

1. Neon
2. Sulphur
3. Sodium
4. Argon

Among period 2 elements, the element which has highest electron affinity is :

1. Lithium
2. Carbon
3. Chlorine
4. Fluorine

Ionisation potential increases over a period from left to right because :

1. Atomic radius and nuclear charge increase
2. Atomic radius and nuclear charge decrease
3. Atomic radius increases and nuclear charge decreases
4. Atomic radius decreases and nuclear charge increases