Question

Atomic number of three elements X, Y,ans Z are4, 13and 18 respectively Identity the group and periods to which these belong​

Answer 1

Answer:

Element X having Z=4 belongs to 2nd period & group 2

Element Y having Z=13 belongs to 3rd period and group 13

Element Z having Z=18 belongs to 3rd period and group 18 or group 0

Explanation:

For Element X,

since the E.C of X is equal to 2,2 the outermost shell or valence shell contains two electrons and total no. of shells is also 2. Thus, it is placed in period 2 & group 2.

For element Y,

since the E.C. of Y is 2,8,3 the valence shell contains three electrons

and total no. of shell is also 3.Thus it is place in group 13 & period 3.

For Element Z,

since the E.C. of Z is 2,8,8 the valence shell contains 8 electrons and total no. of shell is equal to 3. Thus it is place in group 18 and period 3.

Answer 2

Answer:

at.no name group period

4 -> Be => ||A 2

13 -> Al => |||A 3

18 -> Ar => \/|||A 3