Explain the trend in the first ionisation energies of the group 1 elements
The general trend is a decrease in first ionisation energy, which is because as you descend the group the number of energy levels surrounding the positively charged nucleus increases. This means that the outermost electrons are held further away from the positive nucleus, and experience more shielding from the inner shells. This therefore means that the electrostatic attraction between the positive nucleus and negative outermost electron is weakened, so less energy is required for this attraction to be overcome and the electron to be liberated.
CB
Related Chemistry A Level answers
All answers ▸Explain the principle behind chemically reactive and inert molecules
Why does Benzene require a catalyst to react with Bromine whereas Phenol does not?
Name the type of reaction and outline the mechanism for the reaction of the alcohol (CH3)2CHOH with the acyl chloride CH3COCl. Explain which orbitals take part in the reaction.
Given the following equilibrium: H2O + H2O <-> H3O+ + OH- and the Kw = 10^-14, determine the concentration of OH- species after the addition of 1 mmol of HCl to 1 L of neutral water.