Question -
Answer -
The 1st┬аionizationenthalpy of magnesium is higher than 1st┬аionization enthalpy ofsodium because,
- Magnesium is having greater atomic size than sodium.
- Magnesium is having higher effective nuclear charge than sodium.
Thus, energy requiredto expel an electron from sodium is lower than that in magnesium. Thus, the 1st┬аionizationenthalpy of magnesium is higher than 1st┬аionization enthalpy ofsodium.
The 2nd┬аionizationenthalpy of magnesium is lower than 2nd┬аionization enthalpy ofsodium is because after expelling an electron, there is still 1 electronremaining in the 3s-orbital of magnesium, whereas sodium achieves stable inertgas configuration after expelling an electron. So, magnesium still requires toexpel 1 electron to achieve stable inert gas configuration.
Thus, energy requiredto expel 2nd┬аelectron from magnesium is lower than that insodium. Thus, the 2nd┬аionization enthalpy of magnesium is lowerthan 2nd┬аionization enthalpy of sodium.