Question

Identify the smallest atom in each set below (a, b, and c). Then choose the answer (A - D).

a. Ra, Be, Mg
b. Si, Re, V
c. Br, As, Se
A. a: smallest - Ra; b: smallest = Re: c: smallest - As
B. a: smallest = Mg: b: smallest - V; c smallest - Se
C. a: smallest - Be; b: smallest - Si: c: smallest - Br
D. a: smallest - Ra; b: smallest - Si; c: smallest - As

Answer 1

C is the correct answer.

Step-by-step explanation:

In a Ra , Be, Mg is given . These are belong from 2nd group . In moving downwaed to the group no. of shell increase so size of atom increase . S0 the order of these in incresing size is Be<Mg<Ra .

So Be is m=smallest in a .

simillarly order of b in increasing size Si<V<Re .

So Si is smallest .

order of c is Br<As<Se .

These belong from same period an in along the period size decreases due to increase of electrons .