Question

The atomic radius of elements increases on moving down a group because

• A. nuclear charge increases
• B. atomic mass increases
• C. added electrons are accomodated in new electron shells
• D. atomic number increases

Answer 1

The correct option is C

added electrons are accomodated in new electron shells

1. the greater effective nuclear charge attracts more electrons, drawing the electron cloud pretty close to the nucleus and resulting in a smaller atomic radius.
2. The radius of an atom grows in proportion to its atomic number. This is especially true as you move down a given column of the periodic table; the radius of each successive neighboring atom increases.
3. As the number of shells increases, the atomic radius increases accordingly. Hence option C is correct