Explain the trend in ionisation energies for the group one metals?

The first ionisation energy of an element is the minimum energy required to remove a single electron from one mole of an element in its gaseous state. As you go down the group the first electron becomes easier to remove, and therefore less energy is required to remove it, this is for a number of reasons. The first reason is the radius of the atom. As you go down the group, the outer most negative electron is further from the positive central nucleus, this means that the attraction between the electron and the nucleus is decreased, and therefore less energy is needed to remove it. Also, the shielding from inner electrons changes the ionisation energy. As you go down the group, the elements have a greater number of electron shells, this results in there being more electrons blocking the outer electron, so the electrostatic attraction between the nucleus and outer electron is decreased, hence the lower ionisation energy.

DC
Answered by Dan C. Chemistry tutor

1746 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

A buffer was made by mixing 20cm3 of 0.05M NaOH and 20cm3 of 0.25M propanoic acid. Calculate the pH. Ka=1.34x10^-5


The reversible reaction of sulfur dioxide and oxygen to form sulfur trioxide is shown below. 2SO2(g) + O2(g) 2SO3(g) An equilibrium mixture contains 2.4mol SO2, 1.2mol O2 and 0.4mol SO3. The total pressure is 250atm. What is the p(SO3)?


What is entropy?


There are two methods of ionisation in a time of flight spectrometer, name and explain one of these methods in detail.


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences