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

\[\ce{HC ≡ CH ->[HgSO4][H2SO4] ->[CH3MgBr][H2O] ->[PBr3]}\]

The product of acid catalysed hydration of 2-phenylpropene is:

NaCl type crystal (with coordination no. 6 : 6) can be converted into CsCl type crystal (with coordination no. 8 : 8) by applying ____________.

How many chloride ions are surrounding sodium ions in sodium chloride crystal?

The number of moles of NaCl in 3 litres of 3 M solution is ____________.

4 L of 0.02 M aqueous solution of NaCl was diluted by adding one litre of water. The molality of the resultant solution is ______.

Cone. H₂SO₄ is 98% H₂SO₄ by mass has d = 1.84 g cm⁻³. Volume of acid required to make one litre of 0.1 M H₂SO₄ is:

What is the mole fraction of solute in 1.00 m aqueous solutions?

\[\begin{array}{cc}
\ce{CH3-CH-CH=CH2 + HBr -> A}\\
|\phantom{.....................}\\
\ce{CH3}\phantom{..................}
\end{array}\]

'A' is:

The heating of phenyl methyl ether with HI produces:

Which of the following gives a positive iodoform test?

\[\ce{Phenol ->[Zn, dust] 'X' ->[CH3Cl][Anhy. AlCl3] 'Y' ->[Alkaline][KMnO4] 'Z'}\]

The product ‘Z’ is:

Among the following sets of reactants which one produces anisole?

IUPAC name of the compound is:

\[\begin{array}{cc}
\ce{CH3-CH-OCH3}\\
|\phantom{....}\\
\ce{CH3}\phantom{..}
\end{array}\]

The correct acidic strength order of the following is:

     (I)

    (II)

     (III)

Which of the following is a correct statement for C₂H₅Br?

Given below are two statements labelled as Assertion (A) and Reason (R).

Assertion (A): Molarity of a solution changes with temperature.

Reason (R): Molarity is a colligative property.

Select the most appropriate answer from the options given below:

Which of the following is not true about the ionic solids?

An excess of potassium ions makes KCl crystals appear violet or lilac in colour since:

(i) some of the anionic sites are occupied by an unpaired electron.

(ii) some of the anionic sites are occupied by a pair of electrons.

(iii) there are vacancies at some anionic sites.

(iv) F-centres are created which impart colour to the crystals.

Which of the following cannot be regarded as molecular solid?

(i) SiC (Silicon carbide)

(ii) AlN

(iii) Diamond

(iv) I₂