The decreasing order of the second ionization energies of K, Ca and Ba is
Correct answer: A. K>Ca>Ba
- A. K>Ca>Ba
- B. Ca>Ba>K
- C. Ba>K>Ca
- D. K>Ba>Ca
Explanation
The second ionization energy is the energy required to remove a second electron from an atom. Potassium (K) has the highest second ionization energy because once the first electron is removed, it attains a noble gas configuration, making it very stable and requiring more energy to remove another electron. Calcium (Ca) follows because although it also attains a relatively stable state, the electron is removed from a higher energy level. Barium (Ba), being in a lower position in the periodic table, has a larger atomic size and increased shielding effect, reducing the energy required to remove a second electron. Hence, the order is K > Ca > Ba.
Last updated
About Periodic Properties and Trends
Periodic properties arise from electron configuration and effective nuclear charge, producing trends in atomic and ionic radius, ionization energy, electron affinity, electronegativity, metallic character and reactivity. Comparisons run across periods and down groups, with attention to common exceptions. The topic also relates these trends to the behavior of s-block and p-block elements.
Practise s-Block and p-Block Elements
1,359 free s-Block and p-Block Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
2. Law of octaves was proposed by
7th period of the periodic table contains normal elements:
(A), (B) and (C) are elements in the third period. The oxide of(A) is ionic, that of (B) is amphoteric and that of (C) is a giant molecule (covalent network). (A), (B) and (C) have atomic numbers in the order:
(A), (B) and (C) are elements in the third short period. Oxide of (A) is ionic, that of (B) is amphoteric and of (C) a giant molecule. (A), (B) and (C) have atomic numbers in the order of:
A gas that reacts with CaO and not with NaHCO3 is: