Question

1. arrange the following sets of elements in order of increasing atomic size a. sn, xe, rb, sr b. rn, he, xe, kr c. pb, ba, cs, al d. f, i, br, cl 15. in each of the following sets of elements, indicate which element has the smallest atomic size a. na, k, rb b. na, si, s c. n, p, as d. n, o, f e. al, ga, tl

Explanation:

Step1: Recall atomic - size trends

Atomic size increases down a group and decreases across a period from left - to - right.

Step2: Analyze part 14a

Sn is in Group 14, Xe is in Group 18, Rb is in Group 1, Sr is in Group 2. Rb and Sr are in the 5th period, Sn is also in the 5th period, and Xe is in the 5th period. In order of increasing atomic size: Xe < Sn < Sr < Rb.

Step3: Analyze part 14b

Rn is in Group 18, He is in Group 18, Xe is in Group 18, Kr is in Group 18. In order of increasing atomic size: He < Kr < Xe < Rn.

Step4: Analyze part 14c

Pb is in Group 14, Ba is in Group 2, Cs is in Group 1, Al is in Group 13. Cs and Ba are in the 6th period, Pb is in the 6th period, and Al is in the 3rd period. In order of increasing atomic size: Al < Pb < Ba < Cs.

Step5: Analyze part 14d

F is in Group 17, I is in Group 17, Ar is in Group 18, Cl is in Group 17. Ar is a noble gas. In order of increasing atomic size: F < Cl < Ar < I.

Step6: Analyze part 15a

Na, K, Rb are in Group 1. As we go down the group, atomic size increases. So the element with the smallest atomic size is Na.

Step7: Analyze part 15b

Na, Si, S are in the 3rd period. As we move from left - to - right across the period, atomic size decreases. So the element with the smallest atomic size is S.

Step8: Analyze part 15c

N, P, As are in Group 15. As we go down the group, atomic size increases. So the element with the smallest atomic size is N.

Step9: Analyze part 15d

N, O, F are in the 2nd period. As we move from left - to - right across the period, atomic size decreases. So the element with the smallest atomic size is F.

Step10: Analyze part 15e

Al, Ga, Tl are in Group 13. As we go down the group, atomic size increases. So the element with the smallest atomic size is Al.

Answer:

14a: Xe < Sn < Sr < Rb
14b: He < Kr < Xe < Rn
14c: Al < Pb < Ba < Cs
14d: F < Cl < Ar < I
15a: Na
15b: S
15c: N
15d: F
15e: Al