SAMPLE PROBLEM 8.3
Ranking Elements by Atomic Size
PLAN:
SOLUTION:
(a) Ca, Mg, Sr
(b) K, Ga, Ca
(c) Br, Rb, Kr
(d) Sr, Ca, Rb
Size increases down a group; size decreases across a period.
(a) Sr > Ca > Mg
These elements are in Group 2A.
(b) K > Ca > Ga
These elements are in Period 4.
(c) Rb > Br > Kr
Rb has a higher energy level and is far to the left. Br is to the left of Kr.
(d) Rb > Sr > Ca
Ca is one energy level smaller than Rb and Sr. Rb is to the left of Sr.
| Previous slide | Next slide | Back to first slide | View graphic version |