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

Write the main product in the following reaction:

What is ferromagnetism?

Iron (z=26) is highly ferromagnetic. Explain.

What type of magnetism is shown in the following alignment of magnetic moments?

Account for the following: Fluorine does not exhibit positive oxidation state.

Fluorine is a stronger oxidising agent than chlorine. Why?

What type of magnetism is shown by a substance if magnetic moments of domains are arranged in same direction?

What is the difference between a nucleoside and nucleotide?

Compare the oxidizing action of F₂ and Cl₂ by considering parameters such as bond dissociation enthalpy, electron gain enthalpy and hydration enthalpy.

Account for the following :

Acidic character increases from HF to HI.

F₂ has lower bond dissociation enthalpy than Cl₂. Why?

Define the following term:

Ferromagnetism

Which halogen compound in the following pair will react faster in S_N2 reaction CH₃Br or CH₃I.

Which halogen compound in each of the following pairs will react faster in S_N2 reaction

(CH₃)₃ C – Cl or CH₃ – Cl

Write the type of magnetism observed when the magnetic moments are oppositely aligned and cancel out each other.

Write the type of magnetism observed when the magnetic moments are aligned in parallel and anti-parallel directions in unequal numbers.

What type of substances would make better permanent magnets, ferromagnetic or ferrimagnetic. Justify your answer.

Analysis shows that nickel oxide has the formula Ni_0.98O_1.00. What fractions of nickel exist as Ni²⁺ and Ni³⁺ ions?

Explain the following with suitable examples:

Paramagnetism

Explain the following with suitable examples:

Ferrimagnetism