JEE Main PYQs — Classification of Elements & Periodicity

The correct orders among the following are: Atomic radius: B < Al < Ga < In < Tl Electronegativity: Al < Ga < In < Tl < B Density: Tl < In < Ga < Al < B 1st Ionisation Energy: In < Al < Ga < Tl < B…

The property/properties that show irregularity in first four elements of group-17 is/are: (A) Covalent radius (B) Electron affinity (C) Ionic radius (D) First ionization energy Choose the correct…

Given below are two statements: Statement I: The metallic radius of Al is less than that of Ga. Statement II: The ionic radius of Al3+ is less than that of Ga3+. Choose the most appropriate answer:

Electronic configuration of four elements A, B, C and D are given below: (A) 1s2 2s2 2p3 (B) 1s2 2s2 2p4 (C) 1s2 2s2 2p5 (D) 1s2 2s2 2p2 Which of the following is the correct order of increasing…

The nature of oxide (TeO2) and hydride (TeH2) formed by Te, respectively are:

An element 'E' has the ionisation enthalpy value of 374 kJ mol-1. 'E' reacts with elements A, B, C and D with electron gain enthalpy values of -328, -349, -325 and -295 kJ mol-1, respectively. The…

Given below are two statements: Statement I: The radii of isoelectronic species increases in the order: Mg2+ < Na+ < F- < O2- Statement II: The magnitude of electron gain enthalpy of halogen…

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is:

First ionisation enthalpy values of first four group 15 elements are given below. Choose the correct value for the element that is a main component of apatite family:

The incorrect decreasing order of atomic radii is:

Given below are two statements: Statement (I): According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number. Statement (II): Meyer observed a…

Which of the following Statements are NOT true about the periodic table? A. The properties of elements are function of atomic weights. B. The properties of elements are function of atomic numbers. C.…

The atomic number of the element from the following with lowest 1st ionisation enthalpy is:

The correct order of the first ionization enthalpy is:

The element having the highest first ionization enthalpy among Si, Al, N and C is:

In case of isoelectronic species the size of F-, Ne and Na+ is affected by:

The correct order of first ionization enthalpy values of the following elements is: (A) O (B) N (C) Be (D) F (E) B

The electron affinity values are negative for: A. Be -> Be- B. N -> N- C. O -> O2- D. Na -> Na- E. Al -> Al-

The correct sequence of electron gain enthalpy of the elements listed below is:

Consider elements A', B', C', D' where A' and B' are in Period 2, C' and D' in Period 3; A' and C' are in Group 1, B' and D' are in Group 2. Which of the following is/are true? A. Order of atomic…

Henry Moseley studied characteristic X-ray spectra of elements. The graph which represents his observation correctly is: (Given: v = Frequency of X-ray emitted, Z = Atomic number)

It is observed that characteristic X-ray spectra of elements show regularity. When frequency to the power 'n' i.e. vn of X-rays emitted is plotted against atomic number Z, the following graph (a…

For elements B, C, N, Li, Be, O and F, the correct order of first ionisation enthalpy is:

Which of the following statements are not correct? A. The electron gain enthalpy of F is more negative than that of Cl. B. Ionization enthalpy decreases in a group of periodic table. C. The…

The correct increasing order of the ionic radii is:

Which one of the following elements will remain as liquid inside pure boiling water?

Group-13 elements react with O2 to form oxides of type M2O3. Which among the following is the most basic oxide?

The correct order of electronegativity for given elements is:

The correct order of metallic character is:

For electron gain enthalpies of the elements denoted as egH, the incorrect option is:

For compound having the formula GaAlCl4, the correct option from the following is:

Element 'E' belongs to period 4 and group 16 of the periodic table. The valence shell electron configuration of the element which is just above 'E' in the group is:

The correct order of ionic size of N3-, Na+, F-, Mg2+ and O2- is:

The IUPAC nomenclature of an element with electronic configuration [Rn] 5f14 6d1 7s2 is:

The metal that has very low melting point and its periodic position is closer to a metalloid is:

Which of the following is a metalloid?

The first ionization enthalpies of Be, B, N and O follow the order:

Given two statements: Statement I: In Cl2 molecule the covalent radius is double of the atomic radius of chlorine. Statement II: Radius of anionic species is always greater than their parent atomic…

The incorrect statement is:

The correct decreasing order for metallic character is:

The first ionization enthalpy of Na, Mg and Si, respectively, are 496, 737 and 786 kJ mol-1. The first ionization enthalpy (kJ mol-1) of Al is:

Metals generally melt at very high temperatures. Among the following which one has the highest melting point?

What is the correct order of electron gain enthalpy of Cl, F, Te, Po?

Assertion: The ionic radii of O2- and Mg2+ are same. Reason: Both O2- and Mg2+ are isoelectronic species.

In which of the following pairs, electron gain enthalpies of constituent elements are nearly the same or identical? (A) Rb and Cs (B) Na and K (C) Ar and Kr (D) I and At

The correct order of ionic radii for the ions P3-, S2-, Ca2+, K+, Cl- is:

The ionic radii of K+, Na+, Al3+ and Mg2+ are in the order:

The ionic radii of F- and O2- respectively are 1.33 A and 1.4 A, while the covalent radius of N is 0.74 A. The correct statement for the ionic radius of N3- is:

The characteristics of elements X, Y and Z with atomic numbers, respectively, 33, 53 and 83 are:

Which pair of oxides is acidic in nature?

The set in which compounds have different nature is:

The CORRECT order of first ionisation enthalpy is:

Identify the elements X and Y using the ionization energy values given below: | | 1st IE | 2nd IE | |---|---|---| | X | 495 | 4563 | | Y | 731 | 1450 |

The absolute value of the electron gain enthalpy of halogens satisfies:

The ionic radius of Na+ ions is 1.02 Å. The ionic radii (in Å) of Mg2+ and Al3+, respectively, are:

The first ionization energy of magnesium is smaller, as compared to that of elements X and Y, but higher than that of Z. The elements X, Y and Z, respectively, are:

The correct order of electron gain enthalpy is:

The atomic number of the element unnilennium is:

The elements with atomic numbers 101 and 104 belong to, respectively:

The correct order of the ionic radii of O2-, N3-, F-, Mg2+, Na+ and Al3+ is:

The acidic, basic and amphoteric oxides, respectively, are:

The statement(s) that are correct about the species O2-, F-, Na+ and Mg2+: (A) All are isoelectronic (B) All have the same nuclear charge (C) O2- has the largest ionic radii (D) Mg2+ has the smallest…

In general, the property (magnitudes only) that shows an opposite trend in comparison to other properties across a period is:

Three elements X, Y and Z are in the 3rd period. The oxides of X, Y and Z, respectively, are basic, amphoteric and acidic. The correct order of the atomic numbers of X, Y and Z is:

The five successive ionization enthalpies of an element are 800, 2427, 3658, 35024 and 32824 kJ mol-1. The number of valence electrons in the element is:

The process that is NOT endothermic in nature is:

The electron gain enthalpy (in kJ/mol) of fluorine, chlorine, bromine and iodine, respectively, are:

Within each pair of elements F and Cl, S and Se, and Li and Na, respectively, the elements that release more energy upon an electron gain are:

The third ionization enthalpy is minimum for:

The first ionization energy (in kJ/mol) of Na, Mg, Al and Si respectively are:

The increasing order of the atomic radii of the following elements is: (a) C (b) O (c) F (d) Cl (e) Br

B has a smaller first ionization enthalpy than Be. The correct statements are: (I) It is easier to remove 2p electron than 2s electron. (II) 2p electron of B is more shielded from the nucleus by the…

The IUPAC symbol for the element with atomic number 119 would be:

The group number, number of valence electrons, and valency of an element with atomic number 15, respectively, are:

The element with Z = 120 (not yet discovered) will be a/an:

The size of the isoelectronic species Cl-, Ar and Ca2+ is affected by:

The element having the greatest difference between its first and second ionization energies, is:

In comparison to boron, beryllium has:

In general, the properties that decrease and increase down a group in the periodic table, respectively, are:

When the first electron gain enthalpy ( Heg) of oxygen is -141 kJ/mol, its second electron gain enthalpy is:

The correct order of the atomic radii of C, Cs, Al, and S is:

The correct option with respect to the Pauling electronegativity values of the elements is: