Multiple choice The ionic radii of B3+, Al3+ Si4+ and N3- varies in the order of N3- > Al3+ > B3+ > Si4+ N3- > B3+ > Si4+ > Al3+ N3- > B3+ > Al3+ > Si4+ N3- > Al3+ > Si4+ > B3+ Al3+ > B3+ > Si4+ > N3- Reveal answer Fill a bubble to check yourself D Correct answer Explanation The ionic radii of B3+ = 27 pm, Al3+ = 53.5 pm, Si4+ = 40 pm and N3- = 171 pm. Hence, the ionic radii of B3+, Al3+, Si4+ and N3- varies in the order of N3- > Al3+ > Si4+ > B3+.