Why does the atomic radius of an atom decrease as you go across a period?

The atomic radius is often defined as being one half the distance between the two nuclei in a homonucleur diatomic molecule. In general, there is a decrease in atomic radius as you go across a period. This is because atoms in the same period share the similarity of having their valence electrons in the same sub-shell. The difference that occurs however is that there is an increase in atomic number, and thus nuclear charge. The increase in nuclear charge means a higher attraction is exerted from the nucleus, pulling the electrons closer to the nucleus and thus decreasing the size of the atom.

LE
Answered by Louise E. Chemistry tutor

1745 Views

See similar Chemistry IB tutors

Related Chemistry IB answers

All answers ▸

Explain whether the boiling point of 1-bromopentane will be higher, lower or the same as that of 2-bromo-2-methylbutane. (3)


Draw the full curly mechanism for the reaction between Bromo-Methane and NaOH. What reaction is it?


What is the difference between SN1 and SN2 reactions, and how do you determine via which mechanism the reaction will proceed?


Forgot to put question for the interview


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning