Put in order from smallest to largest radii: 1. AI, Na, CI, Ar, Mg
2. S, Te, Po, Se, O
3. Cl, Ca, S, P, Ga, Mg
4. F, CI, Br, I, At

1. Ar, Cl, Al, Mg, Na

2. O, S, Se, Te, Po

Explanation:

Just remember the trends. From left to right, atomic radius decreases because proton increases and pulls electrons closer. From top to bottom, atomic radius increases because there are more electron shells.

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: