Question

TEST 2. Answer the following questions:

1. How do metals obey the octet rule?

2. How do non-metals obey the octet rule?

3. What happens to an atom’s size when it looses an electron?Why?

4. How will you compare the size of the anion with the size of its parent atom?

5. How will you compare the size of the cation with the size of its parent atom?

Answer 1

1. Metals of I and II A groups elements obey octet configuration by loosing 1 and 2 electrons respectively

Ex: Na, it loose one electron and forms Na⁺ following inert gas (Ne) configuration.

2. Non metals obey octet configuration by gaining one or two electrons.

Ex: Oxygen, has 6 valence electrons and by gaining 2 electrons it gets octet configuration, similarly Halogens also gains one electron to get octet configuration .

3. By loosing one electron atoms size will decreases, since the distance between nucleus and valence shell electrons will decreases.

4. Size of anion is more than its parent atom

Ex: Cl has 17 electrons and it forms Cl^- by gaining one electron and has a total of 18 electrons. So, with the increase o elecrons , size also increases.

5. Size of cation is less than the parent atom since cation has less no of electrons than parent atom

Ex: Na > Na⁺ order of size.