19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
IE1 and IE2 of Mg(g) are 178 and 348 kcal mol–1 respectively. The energy required for the reaction Mg (g) ® Mg²⁺ (g) + 2e– is
In which of the following sets of elements, they have nearly the same atomic size
Which of the following isoelectronic ions has the lowest ionization energy?
Consider the isoelectronic species, Na⁺, Mg²⁺,F –and O₂–. The correct order of increasing length of their radii is ...........
Of the following orders of relative sizes, choose the incorrect order
Which of the following represents an excited state of an atom?
La (Lanthanum) having atomic number 57 is a member of:
The period number in the long form of the periodic table is equal to
Of the following which will have the minimum atomic radius?
The statement that is not correct for periodic classification of elements is:
The lower electron affinity of fluorine than that of chlorine is due to
A, B, and C are hydroxy-compounds of the elements X, Y, and Z respectively. X, Y, and Z are in the same period of the periodic table. A gives an aqueous solution of pH less than seven. B reacts with both strong acids …
The element with lowest electron gain enthalpy is:
The most ionic compound will be formed between:
Assertion: Third ionization energy of sulphur is larger than phosphorous. Reason: There is a larger amount of stability associated with filled s- and p- sub-shells (a noble gas electron configuration) which correspond…
Assertion: Generally, ionization enthalpy increases from left to right in a period. Reason: When successive electrons are added to the orbitals in the same principal quantum level, the shielding effect of the inner co…
Assertion: Electron gain enthalpy becomes less negative as we go down a group. Reason: The size of the atom increases on going down the group and the added electron would be farther from the nucleus.
The element with highest I.E. is:
If the Aufbau principle had not been followed, Ca (Z = 20) would have been placed in the:
Which of the following properties shows a gradual decrease with an increase in atomic number across a period in the periodic table?
Consider the following statements: (I) The radius of an anion is larger than that of the parent atom. (II) The ionization energy generally increases with the increasing atomic number in a period. (III) The electronega…
Compound (B) is:
Compound (A) is:
Aluminium becomes passive in:
Which one of the following metals cannot be extracted by using Al as a reducing agent?