Question

the third Period of the modern periodic table has the element aluminium and chlorine as members. to which group do they belong compare their atomic sizes and electronegativity values. state the nature of their oxides .​

Answer 1

Answer:

Al belong to 13 group and Cl belongs to 17 group

Answer 2

Answers about aluminium and chlorine are given below-

Aluminium and chlorine both belong to period 3. The group to which they belong are, 13 for former and 17 for latter.

Atomic size of elements decreases across the period. The reason is increase in number of electrons for same nucleus, thus increasing attractive power.

Electronegativity increases across the period as the atomic radius decreases. It is the ability to attract electrons, so nuclear power increases.

Amount of electrons required to complete the octet decreases. Thus, electronegativity increases.

Chlorine forms acidic oxide while aluminium forms amphoteric oxide. Amphoteric oxide means it can neutralize both acidic and basic compounds.