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The number of Faradays (F) required to produce 20g of Calcium from molten CaCl2 is:

(A) 1 (B) 2 (C) 3 (D) 4 The Correct Answer is (A) 1. Solution: w = Z * Q Explore more such questions and answers at BYJU'S.... View Article

Calculate the percentage of p-character in the orbital occupied by the lone pairs in water molecules : [Given:∠HOH is 104.5∘ and cos (104.5)= − 0.25]

(A) 20% (B) 70% (C) 75% (D) 80% The Correct Answer is (B) 70%. Solution: Hence, i = 4 Also, Here f'p represents the fraction of... View Article

After completion of the reactions (I and II), the organic compound(s) in the reaction mixtures is(are):

(A) Reaction I : P and Reaction II : P (B) Reaction I: T, U, acetone and Reaction II : P (C) Reaction I: U, acetone and Reaction II: Q, acetone... View Article

For the reaction 2P + Q = R. 8 mol of P and 5 mol of Q will produce______.

(A) 4 mol of R (B) 5 mol of R (C) 8 mol of R (D) 13 mol of R The Correct Answer is (A) 4 mol of R. Solution: As given: The... View Article

During an adiabatic compression, 830 J of work is done on 2 moles of a diatomic ideal gas to reduce its volume by 50%. The change in its temperature is nearly [R=8.3 JK-1 mol-1] :

(A) 14 K (B) 20 K (C) 33 K (D) 40 K The Correct Answer is (B) 20 K. Solution: The work done in the adiabatic process is given as:... View Article

The speed of sound in hydrogen at NTP is 1270ms-1. Then the speed in a mixture of hydrogen and oxygen in the ratio 4:1 by volume will be:

(A) 371 ms-1 (B) 380 ms-1 (C) 635 ms-1 (D) 950 ms-1 The Correct Answer is (C) 635 ms-1 Solution: In Hydrogen, In mixture, Now density... View Article

A solid has a BCC structure. If the distance of the nearest approach between two atoms is 1.73 A. What would be the edge length of the cell?

(A) 141 pm (B) 200 pm (C) 216 pm (D) 314.20 pm The Correct Answer is (B) 200 pm. Solution: In BCC structure, the atoms are present one on... View Article

Assertion: The elements with electronic configuration [xe]54 4f1 5d1 6s2 is a d block element. Reason: The last electron enters the d-orbital.

(A) Both Assertion and Reason are false. (B) Assertion is true, but Reason is false. (C) Both Assertion and Reason are true. The reason is... View Article

Which of the following is not an amorphous substance?

(A) Glass (B) Copper (C) Rubber (D) Polymers The Correct Answer is (B) Copper Solution: Copper is not an amorphous substance or... View Article

Using VSEPR theory, draw the shape of PCl5 and BrF5 molecules. Write the state of hybridization of the IRR central atoms.

Solution: The shape of PCl5 molecule. There are five lone pairs of electrons around P. The arrangement of these electrons around P will be a... View Article

Given below are the standard electrode potentials of a few half-cells. K+/K =-2.93 V, Ag+/Ag = 0.80 V, Mg2+/Mg = – 2.37 V,Cr3+/Cr = – 0.74 V. What will be the correct order of these metals in increasing reducing power?

Given:K+/K =-2.93 V, Ag+/Ag = 0.80 V, Mg2+/Mg = - 2.37 V,Cr3+/Cr = - 0.74 V. (A) K < Mg < Cr < Ag (B) Mg < K < Cr < Ag... View Article

Which among the following is an odd electron molecule?

(A) NO (B) NO2 (C) ClO2 (D) All of these The Correct Answer is (D) All of these. Solution: NO, NO2 and ClO2 are odd electron molecules... View Article

What weights of P4O6 and P4O10 will be produced by the combustion of 31g of P4 in 32g of oxygen leaving no P4O2?

(A) 55 g and 71 g (B) 17.5 g and 19.5 g (C) 2.75 g and 35.5 g (D) 2.75 g and 29.5 g The Correct Answer is (C) 2.75 g and 35.5 g Solution:... View Article

The total energy of an electron in the first excited state of the hydrogen atom is -3.4 eV. Find out its (i) kinetic energy and (ii) potential energy in this state.

Solution: (i) Kinetic energy (KE) Kinetic energy of electron is -- KE = For the first excited state of the hydrogen atom, n = 2 and Z = 1... View Article

Which of the following compounds does not show geometrical isomerism?

(A) 2-butene (B) 2-pentene (C) 2-methyl propene (D) 2-3-dibromo-2-butene The Correct Answer is (C) 2- Methyl Propane Solution: 2−methyl... View Article

Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:

Image (A) I > II > III > IV (B) II > I > III > IV (C) III > IV > II > I (D) IV > I > II > III The... View Article

To carry out a given conversion, Arrange the following reagents in correct order.

(1) H+ (2) O3/Zn (3) NaOCl (4) EtONa / EtOH/ Δ Image (A) 1 → 2 → 3 → 4 (B) 1 → 3 → 2 → 4 (C) 2 → 4 → 3 → 1 (D) 4 → 3 → 2 → 1 The... View Article

Which of the following compounds is most reactive towards nucleophilic addition reaction?

(A) PhCOPh (B) CH3CHO (C) PhCOCPH3 (D) CH3COCH3 The Correct Answer is (B) CH3CHO Solution: The aromatic aldehydes and ketones are... View Article

Which of the following compounds has only a primary hydrogen atom?(A) Butane (B) Isobutane (C) Isopentane (D) Cyclohexane

The Correct Answer is (D) Cyclohexane Solution: The compound having only the primary hydrogen atom is cyclohexane. In Cyclohexane, a carbon... View Article

The correct order of acidity of the following elements is i)Phenol (ii)Methyl phenol (iii)Meta-nitro phenol (iv) Para-nitro phenol

(A) Phenol > Meta-nitrophenol > Methyl phenol > Para-nitrophenol (B) Para-nitrophenol > Meta-nitrophenol > Phenol > Methyl... View Article