Question

1. Specify the group on the periodic table in which each of the following elements is found: a) [Ar]4s¹ b) [Ar]4s²3d¹⁰4p³ c)[Ne]3s²3p³ d) [Ar]4s²3d⁶
2. Answer Question 4.44 from the back of the chapter: On the basis of their positions in the periodic table, select the atom with the larger atomic radius in eachof the following pairs: a) Mg, P; b) Sr, Be; c) As, Br; d) Cl, I; e) Xe, Kr

Answer 1

Here the electronic cinfiguration are here

a. [Ar]4s¹= (Potassium and atomic no-19)

b.[Ar]4s²3d¹⁰4p³⁼ (Arsenic and atomic no is 33)

c.[Ne]3s²3p³= (Phosphorousand atomic 15)

d.[Ar]4s²3d⁶=  (Iron and atomic no 26)

On the basis of the periodic table, move from left to right across a period the atomic size decreases due to increase of nuclear charges and the atomic size increases from up to down along a group due to increase the shell number.By using this concept we have :

a. From and = has large atomic size beacuse Mg and P both comes in same period.

b. From and = has large size because both comes in one group

c. From and = has large size and both comes in same period.

d. From and = has large size and both come in one group

e. From and = has large size and both comes in one group