Explain why ionisation enthalpies decrease down a group of the periodic table?

Important Questions on Classification of Elements and Periodicity in Properties

MEDIUM

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 32

The first five successive ionisation enthalpies of boron atom are $800,2427,3658,25024$ and $32824 \mathrm{kJ} {\mathrm{mol}}^{-1}$ respectively. Explain these ionisation enthalpies.

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 33

Explain the following :
Ionisation enthalpy of $\mathrm{Mg}$ is more than that of $\mathrm{Na}$ and $\mathrm{Al}$.

MEDIUM

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 33

Explain the following : Ionisation enthalpy of nitrogen is more than that of oxygen.

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 34

Why is the ionisation enthalpy of $\mathrm{Be}$ more than that of $\mathrm{B}$? Explain.

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 35

If we consider ionisation enthalpies of elements in the second period from $\mathrm{Li}$ to $\mathrm{Ne}$, ordinarily increase but $\mathrm{Be}$ and $\mathrm{N}$ have higher ionisation enthalpies than $\mathrm{B}$ and $\mathrm{O}$ respectively, which succeed them. Why is it so?

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 36

Explain the terms ionisation enthalpy and electron gain enthalpy?

MEDIUM

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 37

What do you mean by successive electron gain enthalpies? Why is the second electron gain enthalpy of an atom positive?

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 3 - Classification of Elements and Periodicity in Properties>ADDITIONAL QUESTIONS>Q 38

Explain the term electron gain enthalpy? How does it vary along a group and across a period?