lonisation enthalpies' of Ce, Pr and Nd are higher than Th, Pa and U. Why?

Give justification, The first lonisation enthalpy of carbon is greater than that of boron, whereas the reverse is correct for the second ionisation enthalpy.

The first ionization enthalpy of magnesium is higher than that of sodium. Explain.

a) First ionization enthalpy of Na is lower than that of Mg. But its second ionization enthalpy is higher than that of Mg. Explain. b) Which one is smaller, Na or Na^+ ? Give reason.

How would you explain that the first ionisation energy of Na is lawer than that of Mg but is second inoisation enthalpy is higher than that of Mg ?

The first ionization enthalpy of sodium is lower than that of magnesium but its second ionisation enthalpy is higher than that of magnesium. Explain.

The HNH angle value is higher than HPH, HAsH and HSbH angles. Why?

Transition elements generally have high enthalpy of atomisation and they show variable oxidation states Why do transition elements exhibit higher enthalpies of atomisation?

Ions having same number of electrons are called isoelectronic ions. Out of Na^+ and Ne which has higher ionisation enthalpy. Explain why?

A quantitative measure of the tendency of an element to lose electron is given by its ionisation enthalpy (I.E.). I.E. increases from left to right in a period of the periodic table. However, in second period, the I.E of oxygen is less than that of nitrogen. Why?

a) Which of the following has higher first ionization enthalpy, N or O? Justify. b) Which one is bigger, F or F^- ? Why?