19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
A metal (M) produces a gas (N) on reaction with alkalis like NaOH and KOH. Same gas is produced when the metals react with dilute sulphuric acid. Gas (N) reacts with another toxic gas (P) to form methanol at high temp…
Match the column I with column II and mark the appropriate choice. Column I Column II (A) NaH (i) Interstitial hydride (B) CH4 (ii) Molecular hydride (C) VH0.56 (iii) Ionic hydride (D) B2H6 (iv) Electron-deficient hyd…
Phosphorus cannot form PH5 with its outer electronic configuration as 3s2, 3p3 because
Which of the statements given below are true for the water molecule structure? (i) Oxygen undergoes sp3hybridisation. (ii) Due to presence of two lone pairs of electrons on oxygen the H–O–H bonds angle is 118.4°. (ii…
Choose the correct statement about the given figures.
Match the reaction of column I with their types given in column II and mark the appropriate choice. Column I Column II (A) H O NH NH OH (i) Self ionisation of H2O (B) FeCl 3H O -> Fe(OH) 3HCl (ii) Decompositio…
Study the following reactions and mark the correct properties shown by water. (i) SO3 + H2O → H2SO4 (ii) Cl2O7 + H2O →2HClO4 (iii) CaO + H2O →Ca(OH)2 (iv) Na2O + H2O →2NaOH
During hydrate formation from aqueous solution, water can be associated in different forms. Indicate the wrong combination. (i) Coordinated water – [Cr(H2O)6]3+ 3Cl– (ii) Interstitial water – BaCl2.2H2O (iii) Hydrogen…
A commercial sample of hydrogen peroxide is labelled as 10 volume. Its percentage strength is nearly
Assertion: Increasing pressure on pure water decreases its freezing point. Reason: Density of water is maximum at 4° C.
Assertion: Among the two OH bonds in H2O molecule, the energy required to break the first OH bond and the other OH bond is same. Reason: This is because the electronic environment around oxygen is the same even after …
Assertion: Permanent hardness of water can be removed by using washing soda. Reason: Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates.
Assertion: Anhydrous BaO2 (barium peroxide) is used for preparing H2O2. Reason: Hydrated BaO2 is not available.
Assertion: In alkaline medium, H2O2 reacts with potassium ferricyanide. Reason : H2O2 is a strong reducing agent.
At its melting point, ice is lighter than water because (AIPMT 1992)
Hydrogen peroxide molecules are (AIPMT 1991)
The ionization of hydrogen atom would give rise to (AIPMT 1990)
Which of the following metals evolves hydrogen on reacting with cold dilute HNO3? (AIPMT 1989)
When CO2 is bubbled through a solution of barium peroxide in water
Given below are two reactions of water with sodium and carbon dioxide. What is the nature of water in these reactions? (i) 2Na + 2H2O -> 2NaOH + H2 (ii) 6CO2 + 12H2O -> C6H12O6 + 6H2O + 6O2
Which gas is produced when calcium nitride (Ca3N2) is hydrolysed by water?
Liquid water is denser than ice due to
The density of water is less in its solid state because
Water plays a key role in the biosphere. It is due to certain properties of H2O as compared to other liquids. Which of these is not a correct property of water?
Which is not a property of water ?