NEET 2026
- Exam
- NEET
- Year
- 2026
- Subject
- Chemistry
- Chapter
- Chapter
NEET 2026 · Chemistry · Chapter
Given below is an outline of the modern periodic table where four...
Given below is an outline of the modern periodic table where four elements are marked as P, Q, R, and S.
Match List I (the marked elements) with List II (their characteristic properties) based on their positions in the periodic groups.
| List I | List II | ||
|---|---|---|---|
| A | Element P | I | Highest negative electron gain enthalpy |
| B | Element Q | II | Most electronegative element |
| C | Element R | III | Lowest ionization enthalpy |
| D | Element S | IV | Highest ionization enthalpy |
Identify the correct answer from the options given below:
Options
- AA-III, B-I, C-II, D-IV
- BA-III, B-II, C-I, D-IV
- CA-IV, B-II, C-I, D-III
- DA-III, B-I, C-IV, D-II
Correct answer
B. A-III, B-II, C-I, D-IV
Step-by-step solution
Based on the given outline of the modern periodic table, the elements are identified as follows:
Element P is in Group 1 and Period 6, which corresponds to Cesium (Cs). Cesium has the largest atomic size among stable elements and consequently the lowest ionization enthalpy. Thus, A matches with III.
Element Q is in Group 17 and Period 2, which corresponds to Fluorine (F). Fluorine is the most electronegative element in the periodic table. Thus, B matches with II.
Element R is in Group 17 and Period 3, which corresponds to Chlorine (Cl). Chlorine has the highest negative electron gain enthalpy due to its relatively smaller size and higher effective nuclear charge compared to other halogens, but larger size than fluorine which reduces interelectronic repulsions. Thus, C matches with I.
Element S is in Group 18 and Period 1, which corresponds to Helium (He). Helium has a completely filled shell and the smallest atomic size among noble gases, giving it the highest ionization enthalpy of all elements. Thus, D matches with IV.
The correct matching is A-III, B-II, C-I, D-IV.
Answer: A-III, B-II, C-I, D-IV
Element P is in Group 1 and Period 6, which corresponds to Cesium (Cs). Cesium has the largest atomic size among stable elements and consequently the lowest ionization enthalpy. Thus, A matches with III.
Element Q is in Group 17 and Period 2, which corresponds to Fluorine (F). Fluorine is the most electronegative element in the periodic table. Thus, B matches with II.
Element R is in Group 17 and Period 3, which corresponds to Chlorine (Cl). Chlorine has the highest negative electron gain enthalpy due to its relatively smaller size and higher effective nuclear charge compared to other halogens, but larger size than fluorine which reduces interelectronic repulsions. Thus, C matches with I.
Element S is in Group 18 and Period 1, which corresponds to Helium (He). Helium has a completely filled shell and the smallest atomic size among noble gases, giving it the highest ionization enthalpy of all elements. Thus, D matches with IV.
The correct matching is A-III, B-II, C-I, D-IV.
Answer: A-III, B-II, C-I, D-IV