Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Chemistry

Which is the strongest acid in the following:

Which of the following pairs of ions are isoelectronic and isostructural?

Bond dissociation enthalpy of E–H (E = element) bonds is given below. Which of the compounds will act as the strongest reducing agent?

In which of the following cases blood cells will shrink ______.

Which of the following arrangements shows schematic alignment of magnetic moments of antiferromagnetic substances?

Which of the following statements is not true?

A ferromagnetic substance becomes a permanent magnet when it is placed in a magnetic field becuase ______.

The value of magnetic moment is zero in the case of antiferromagnetic substances because the domains:

(i) get oriented in the direction of the applied magnetic field.

(ii) get oriented opposite to the direction of the applied magnetic field.

(iii) are oppositely oriented with respect to each other without the application of magnetic field.

(iv) cancel out each other’s magnetic moment.

Which of the following statements are correct?

(i) Ferrimagnetic substances lose ferrimagnetism on heating and become paramagnetic.

(ii) Ferrimagnetic substances do not lose ferrimagnetism on heating and remain ferrimagnetic.

(iii) Antiferromagnetic substances have domain structures similar to ferromagnetic substances and their magnetic moments are not cancelled by each other.

(iv) In ferromagnetic substances all the domains get oriented in the direction of magnetic field and remain as such even after removing magnetic field.

Which of the following binary mixtures will have same composition in liquid and vapour phase?

(i) Benzene - Toluene

(ii) Water-Nitric acid

(iii) Water-Ethano

(iv) n-Hexane - n-Heptane

Components of a binary mixture of two liquids A and B were being separated by distillation. After some time separation of components stopped and composition of vapour phase became same as that of liquid phase. Both the components started coming in the distillate. Explain why this happened.

How does a delta form at the meeting place of sea and river water?

In solid state \[\ce{PCl5}\] is a ______.

Reduction potentials of some ions are given below. Arrange them in decreasing order of oxidising power.

Which of the following is isoelectronic pair?

Which of the following statements are true?

(i) Only type of interactions between particles of noble gases are due to weak dispersion forces.

(ii) Ionisation enthalpy of molecular oxygen is very close to that of xenon.

(iii) Hydrolysis of XeF₆ is a redox reaction.

(iv) Xenon fluorides are not reactive.

Give reason to explain why ClF₃ exists but FCl₃ does not exist.

A hydrocarbon ‘A’, \[\ce{(C4H8)}\] on reaction with \[\ce{HCl}\] gives a compound ‘B’, \[\ce{(C4H9Cl)}\], which on reaction with 1 mol of \[\ce{NH3}\] gives compound ‘C’, \[\ce{(C4H11N)}\]. On reacting with \[\ce{NaNO2}\] and \[\ce{HCl}\] followed by treatment with water, compound ‘C’ yields an optically active alcohol, ‘D’. Ozonolysis of ‘A’ gives 2 mols of acetaldehyde. Identify compounds ‘A’ to ‘D’. Explain the reactions involved.

Which of the following B group vitamins can be stored in our body?

Why must vitamin C be supplied regularly in diet?