The correct order of first ionisation enthalpy is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Barium carbonate is insoluble in water and is highly stable. Reason (R) : The thermal stability of the carbonates increases with increasing cationic size.

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

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Metallic character decreases and non-metallic character increases on moving from left to right in a period. Reason (R) : It is due to increase in ionisation enthalpy and decrease in electron gain enthalpy, when one moves from left to right in a period. In the light of the above statements, choose the most appropriate answer from the options given below :

Match List - I with List - II : List - I (Metal Ion) List - II (Group of Qualitative analysis) (a) $$M{n}^{2+}$$ (i) Group - III (b) $$A{s}^{3+}$$ (ii) Group - IIA (c) $$C{u}^{2+}$$ (iii) Group - IV (d) $$A{l}^{3+}$$ (iv) Group - IIB Choose the most appropriate answer from the options given below :

(A) HOCI + H2O2 → H3O+ + Cl- + O2 (B) I2 + H2O2 + 2OH- → 2I- + 2H2O + O2 Choose the correct option.

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason R : Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below :

Which of the following equation depicts the oxidizing nature of H2O2?

Water does not produce CO on reacting with :

Statements about heavy water are given below : A. Heavy water is used in exchange reactions for the study of reaction mechanisms. B. Heavy water is prepared by exhaustive electrolysis of water. (C) Heavy water has higher boiling point than ordinary water. (D) Viscosity of H2O is greater than D2O. Choose the most appropriate answer from the options given below :

Given below are two statements : Statement I : H2O2 can act as both oxidising and reducing agent in basic medium. Statement II : In the hydrogen economy, the energy is transmitted in the form of dihydrogen. In the light of the above statements, choose the correct answer from the options given below :

The correct statements about H2O2 are : (A) used in the treatment of effluents. (B) used as both oxidising and reducing agents. (C) the two hydroxyl groups lie in the same plane. (D) miscible with water. Choose the correct answer from the options given below :

The INCORRECT statement(s) about heavy water is (are) (A) used as a moderator in nuclear reactor (B) obtained as a by-product in fertilizer industry (C) used for the study of reaction mechanism (D) has a higher dielectric constant than water Choose the correct answer from the options given below :

The functional groups that are responsible for the ion-exchange property of cation and anion exchange resins, respectively, are :

In basic medium, H2O2 exhibits which of the following reactions? (A) Mn2+ $$\to$$ Mn4+ (B) I2 $$\to$$ I$$-$$ (C) PbS $$\to$$ PbSO4 Choose the most appropriate answer from the options given below :

Given below are two statements : One is labelled as Assertion A and other is labelled as Reason R. Assertion A : The dihedral angles in H2O2 in gaseous phase is 90.2$${}^{\circ }$$ and in solid phase is 111.5$${}^{\circ }$$. Reason R : The change in dihedral angle in solid and gaseous phase is due to the difference in the intermolecular forces. Choose the most appropriate answer from the options given below for A and R.

The single largest industrial application of dihydrogen is :

The water having more dissolved O2 is :

At 298.2 K the relationship between enthalpy of bond dissociation (in kJ mol$$-$$1) for hydrogen (EH) and its isotope, deuterium (ED), is best described by :

The number of neutrons and electrons, respectively, present in the radioactive isotope of hydrogen is :