The following reaction of benzene with carbon monoxide and hydrogen chloride in the presence of aluminum trichloride to give benzaldehyde is known as

Arrange the following elements in decreasing order of their radii:
(A) La
(B) Pr
(C) Gd
(D) Yb
Choose the correct answer from the options given below:

Answer the question on the basis of passage given below:
Second period elements of p-Block differs from the rest of their group members due to their small atomic size, high electronegativity, high ionization enthalpy and absence of d-orbitals. The elements from the second period like C, N, O have unique property of forming \(p \pi-p \pi\) multiple bonds whereas other heavier elements of p-block form \(d \pi-p \pi\) multiple bonds. This changes the properties of second period elements to great extent. Also the single bond strength of the p-block elements with their own atoms gets affected by their atomic size and presence of lone pairs.
Inert pair effect also affects the properties of the p-Block elements especially for those elements which are present from 4th period onward and this happens due to poor screening effect of inner (n-1)d subshell electrons.
\(\text{N}_2\) is a gas wherein \(\text{P}_4\) is a solid, because -

The intermediate compound \(\text{[A]}\) is :

Which of the pair(s) are correctly matched?

Colloid Type	Example
(A) Liquid in solids	Gem stones
(B) Solid in liquid	Cell fluids
(C) Solid in Gas	Mist
(D) Gas in liquid	Pumice stone
(E) Liquid in Solid	Butter

Choose the correct answer from the options given below :

Answer the question on the basis of passage given below:
In the periodic table, the d-block contains the elements of group \(3\) to \(12\). The d-orbitals are progressively filled in each of the four long periods. The elements of d block referred as transition metals have partly filled d orbitals and exhibit certain characteristic properties such as variety of oxidation states, formation of coloured ions, act as catalyst and show paramagnetic behaviour.
The two inner transition metals series \(4f\) and \(5f\) are known as Lanthanoids and Actinoids respectively. The lanthanoids resemble one another more closely as compared to ordinary transition elements in any series.
The bonds present in the structure of dichromate ion are:

The IUPAC name of the following compound is:

Which of the following is connected to the coil of the galvanometer, to protect it from possible damages due to large current?

Which one among the following shows particle nature of light?

The least positive integer \(x\) satisfying \(29 \equiv x(\bmod 5)\) is

The unit of rate constant for first order reaction is:

If A and B are square matrix of order \(n \times n\), then \((A-B)^2\) is equal to
A. \(A^2-A B-B A+B^2\)
B. \(A^2-2 A B+B^2\)
C. \(A^2-2 B A+B^2\)
D. \(\quad A^2-B^2\)
E. \(A^2+2 A B+B^2\)
Choose the correct answer from the options given below:

If \(y=2 x(x-1)(2-x)\); then \(\frac{d^2 y}{d x^2}\) is: