Explore topic-wise InterviewSolutions in Current Affairs.

Correct Answer is: (c) contract, but its final length will be greater than its initial length

No. The reversibility of the lens makes equation.

Correct Answer is: (c)

(c) (CH₃)₃CNO₂ – 3⁰ nitroalkane

(b) blue solution

(b) N – nitroso methyl phenylamine

(c) Ethyl alcohol

(c) Diazotisation

Today the use of CFC is being controlled in most of the countries. Harmful CFC are replaced nowadays with safer substances this has helped in reducing the rate of depletion of ozone layer.

Ozone is present mostly in the stratosphere of the atmosphere. Atmosphere oxygen dissociates on absorption of high energy ultraviolet radiation. The oxygen atoms thus formed combine together to form 03 molecule.

(a) gravitational force

Chloroflouro carbons are responsible for the depletion of the ozone layer. Chlorofluorocarbon released into the atmosphere reach the stratosphere and breakdown by the action of ultraviolet radiation releasing chlorine the chlorine decomposes ozone molecules into oxygen. This disturbs the equilibrium in the ozone – oxygen cyclic process. Hence the depletion of ozone in the atmosphere reduces the absorption of ultraviolet rays.

Correct answer is (d) Newton

1) Displacement (s) = Area of the graph = Area of ABDO rectangle + BDC triangle. 

2) Area of the rectangle ABDO = 8 × 20 = 160. 

3) Area of the triangle BDC =1/2 × 20 × (12 – 8) 

= 1/2 × 20 × 4 = 40. 

4) Displacement (s) = 160 + 40 = 200 m.

5) Hence, displacement of the object in 12 sec. = 200 m.

संस्तब्ध वोल्टेज, V₀= 1.5 V 

प्रकाश इलेक्ट्रॉनों की उच्चतम गतिज ऊर्जा, 

Eℜ = eV₀ = 1.5 ev = 1.5 x 16 x 10^-19J = 2.4 x 10^-19J

Correct answer is (b) conservative

TNB is formed when 1, 3, 5 – trinito toluene is treated with acidified Na₂Cr₂O₇ and sodalime.

Acetic anhydride: 

It is an acid derivative whereas others are organic nitrogen compounds.

Aspirin:

It is acid derivative and used as medicine whereas other are organic nitrogen compounds used in medicine.

(d) p – amino azo benzene

Glyceryl triacetate:

It is a an ester of glycerol whereas others are organic nitrogen compounds used in making explosives.

Propan – 2 – amine: 

It is a secondary amine whereas others are tertiary amines.

N,N – dimethyl methanamine: 

It is an example of tertiary amine whereas others are secondary amine.

(c) Schotten – Baumann reaction

(a)  3 4 2 1

(b)  4 1 2 3

Let the barometer has a length = x
Height of air above the mercury column = (x – 74 – 1) = (x – 73)
Pressure of air = 76 – 74 – 1 = 1 cm
For 2^nd case height of air above = (x – 72.1 – 1 – 1) = (x – 71.1)
Pressure of air = (74 – 72.1 – 1) = 0.99 (x – 73)(1) =9/10(x – 71.1)        => 10(x – 73) = 9 (x – 71.1)
=> x = 10 × 73 – 9 × 71.1 = 730 – 639.9 = 90.1
Height of air = 90.1
Height of barometer tube above the mercury column = 90.1 + 1 = 91.1 mm

Data : λ₁ = λ₂ , v₁ = 4v₂

λ = \(\cfrac{h}p\) = \(\cfrac{h}{mv}\)

∴ λ₁ = \(\cfrac{h}{m_1v_1}\), λ₂ = \(\cfrac{h}{m_2v_2}\)

∴ m₁ = m₂ \(\cfrac{v_2}{v_1}\) = m₂ \((\cfrac{1}4)\) = \(\cfrac{m_2}4\)

As particle 2 is the a-particle, particle 1 (having the mass \(\cfrac{1}4\) times that of the a-particle) may be a proton or neutron.

Correct option is (D) β-particle

Ethanol is a good solvent which makes it suitable for preparing medicines.

• The general electronic configuration of 4f-series elements is, Ln[Xe]⁵⁴ 4f^1-14 5d^0-1 6s² where Ln is a lanthanoid.
• Xenon has electronic configuration, [Xe] : Is² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶. 
• In lanthanoids, the differentiating electron enters prepenultimate shell, 4f m

(c) Poor shielding effect of 4f sub-shell

(c) Yb and Lu

Gd have half-filled 4f orbital.

The most common oxidation state of Lanthanoids is +3

3 is most common among the lanthanoids

(d) [Xe] 4f^2-14 5d^1-10 6s²

(a) Cold dilute alkaline KMnO₄

. The common oxidation state of lanthanoids is +3. In addition to that some of the lanthanoids also show either +2 or +4 oxidation states. 

2. Gd³⁺ and Lu³⁺ ions have extra stability, it is due to half filled and completely filled f-orbitals. 

3. Cerium and terbium attain 4f⁷ and 4f¹⁴ configurations respectively in the +4 oxidation states. 

4. Eu²⁺ and Yb³⁺ ions have exactly half filled and completely filled f orbitals. 

5. Lu shows only +3 oxidation state. 

6. Ce, Pr, Nd, Tb and Dy exhibit +3 and +4 oxidation states.

7. Nd, Sm, Eu, Tm, Yb exhibit +2 oxidation states also.

1. Cold dilute alkaline KMnO₄ is known as Baeyer’s reagent. It is used to oxidise alkene into diols.

2. For example, ethylene can be converted into ethylene glycol and this reaction is used as a test for unsaturation.

1. In the presence of dilute sulphuric acid, potassium permanganate acts as a very strong oxidising agent. Permanganate ions is converted into Mn⁺ ion. 

MnO₄^- + 8H⁺ +5e^- → Mn²⁺ + 4H₂O 

Example: 1. Potassium permanganate oxidises ferrous salts to ferric salts.

2. Potassium permanganate oxidises iodide ions to iodine. 

2MnO₄^-  + 10I^-+ 16H⁺ → 2Mn²⁺ + 5I₂ + 8H₂O 

3. Potassium permanganate oxidises sulphide ion to sulphur. 

2MnO₄^-  + 5S^_2- + 16H⁺ → 2Mn²⁺ + 5S + 8H₂O 

4. Potassium permanganate oxidises oxalic acid to CO₂.

2MnO₄^-  +  5(COO)^2- + 16H⁺ → 2Mn²⁺ + 10CO₂ + 10H₂O 

5. Potassium permanganate oxidises alcohols to aldehyde.

2KMnO₄ + 3H₂SO₄ + 5CH₃CH₂OH → 2K₂SO₄ + 2MnSO₄ + 5CH₃CHO + 8H₂O

(b) unsaturated organic compound

1. Nucleophilic substitution (or) Schotten Baumann

2. Secondary amine

3. Carbylamine reaction (or) Hoffmann mustard oil reaction

4. dark coloured tars

5. Free radical chain

6. Phenol

7. Gomberg

8. Para

9. Levine and hauser

10. insecticide

Ethanol has higher boiling point than methoxymethane dur to formation of intermolecular Hydrogen bond in ethanol.

a.Due to presence of intermolecular hydrogenbond in ethanol.

b. Due to –R effect of phenoxide ion produced after the loss of proton from phenol, phenoxide ion is more stable than alkoxide ion.

B. they had been tricked by Taro.

D. Both A and B

A. all his neighbours there with pitchers, jars and buckets.

That evening there was a long procession of visitors to the woodcutter’s house. Each man heard the story of the waterfall, and took a sip of the sake. In less than an hour the pitcher was empty.

At the age of 14, Bismillah accompanied his uncle to the Allahabad Music Conference. At the end of his recital, Ustad Faiyaz Khan patted the young boys back and said, “Work hard and you shall make it.”