Question

arrange the following atoms in order of decreasing atomic radius: ga, as, sn, sb, te
a ga; as, sn, sb, te
b te, sb, sn, as, ga
c sn, sb, te, as, ga
d sn, sb, te, ga, as
e te, sb, as, sn, ga

Explanation:

Step1: Recall atomic - radius trends

Atomic radius decreases across a period (left - to - right) and increases down a group.

Step2: Locate elements in the periodic table

Ga is in Group 13, Period 4; As is in Group 15, Period 4; Sn is in Group 14, Period 5; Sb is in Group 15, Period 5; Te is in Group 16, Period 5.

Step3: Compare periods

Since Sn, Sb, and Te are in Period 5 and Ga and As are in Period 4, the elements in Period 5 are generally larger due to an additional energy level.

Step4: Compare within periods

Within Period 4, Ga > As (atomic radius decreases left - to - right). Within Period 5, Sn > Sb > Te (atomic radius decreases left - to - right).

Step5: Arrange in decreasing order

Combining the above, the order of decreasing atomic radius is Sn > Sb > Te > Ga > As.

Answer:

d. Sn, Sb, Te, Ga, As