Explore topic-wise InterviewSolutions in .

1. < (less than) 

2. < (less than)

1. Prop-1-ene 

2. Butr-2-yne 

3. Ethan-1-al

(i) C (Because pH 7 is neutral). 

(ii) B (Because acids liberate CO₂ gas when treated with carbonates and acids have pH less than 7) 

(iii) A (Bases turn red litmus blue and they have pH more than 7)

Aqueous ferrous nitrate when treated with NaOH solution gives a dirty green ppt.

Aqueous lead nitrate when treated with NaOH solution gives a white ppt. which dissolves in excess of NaOH.

When manganese dioxide is heated with conc. HCl, a pungent smelling greenish yellow chlorine gas is evolved. When copper oxide is heated with conc. HCl, no such gas is evolved.

(i) Only ions 

(ii) molecules 

(iii) Ions as well as molecules

(i) (d)

(ii) (a)

(iii) (b) 

(iv) (e) 

(v) (c)

(2)  +6 and+4

CH₃COONa → CH⁺₃ + COONa–

Aqueous solution of CH₃COONa is basic in nature.

H₂O ⇌ H⁺ (aq) + OH^- (aq) ...(i)

At 25°C, [H⁺] = [OH^–] = 1.01 x 10^-7 M.

K_w = 10^-14, K = 1.8 x 10^-6 (at 25°C)

The value of K_w increases with the increase of temperature i.e., the concentration of H⁺ and OH^– ions increases with increase in temperature. Neutral solution pH will increase. 

CH₃COONa → CH⁺₃ + COONa^–

Aqueous solution of CH₃COONa is basic in nature.

Fe³⁺ + e^– → Fe²⁺

3 mole Fe³⁺ will require 3-mole electrons.

Required charge = 3 × 96500 coulomb = 289500 coulomb

Charge = Current × Time

Time \(\frac{Charge}{Current}\) = \(\frac{289500}{2}\) = 1.44750 x 10⁵ sec. = 40 hrs

If the molecular formula of an organic compound is C₁₀H₁₈ it is alkyne.

If the molecular formula of an organic compound is CiOH₁₈ it is alkyne

Consists of molecules.

2. consists of molecules

To increase the pH value of neutral solution, we should add an alkali.

(i) Cation that does not form, a precipitate with ammonium hydroxide but forms one with sodium hydroxide- Ca²⁺

(ii) The electrolyte used for electroplating an article with silver -  Solution of sodium argentocyanide.

(iii) The particles present in a liquid such as kerosene, that is a non-electrolyte - Molecules.

(iv) An organic compound containing -COOH functional group - Carbo-xylic acid. 

(v) A solid formed by reaction of two gases, one of which is acidic and the other basic in nature - Ammonium chloride (formed by combining vapours of ammonia with hydrogen chloride gas).

3. an alkali

Anhydrous iron (III) chloride is prepared by direct combination.

1. direct combination

Three objectives achieved during the roasting of ores is:

1. It removes moisture from ores.

2. It makes the ore porous and more reactive.

3. It expels volatile impurities.

4. It converts sulphide ores into oxides.

(a) Minerals are naturally occurring compounds of metals which are generally present with other matter such as soil, sand, limestone and rocks. Ores are those minerals from which the metals are extracted commercially at low cost and comfortably. All ores are minerals, but all minerals are not necessarily ores.

(b) Ores are those minerals from which the metals are extracted commercially at low cost and with minimum effort. A metallic compound is a compound that contains one or more metal elements. 

Examples: AgNO₃ - Silver nitrate is a metallic compound.

The metals that can be extracted from the following ores are:

(a) Bauxite- Aluminium

(b) Calamine- Zinc

(c) Hematite- Iron

(D) Ionizes when dissolved in water.

(B) Ionization potential increases from left to right across a period.

Apes: 

1. Posture – Semi erect 

2. Cranium – flattened with cranial capacity under 650 cm3. 

3. Brow ridges – Prominent. 

4. Locomotion-walk semi-erect on the outer edges of the feet and knuckles of hands, soles do not lie flat on the ground.

Man: 

1. Fully erect. 

2. Rounded with a cranial capacity of about 1450 cm3. 

3. Brow ridges-inconspicuous. 

4. Walk fully erect on the soles of feet which lie flat on the ground while walking.

(a) When a new partner is added to a partnership firm. 

(b) At the time of retirement of a partner.

(a) Lump sum method 

(b) Installment method

Calcination is the decomposition of hydroxide and carbonate ores by heating them in absence of air. 

Roasting is oxidation of sulphide ores by heating them in excess of air.

Aluminium is found abundantly in the earth's crust.

(a) Dry air free from carbon dioxide and dry ammonia from Habers process.

(b) The catalyst used in the process is Platinum.

(c) The oxidizing agent used in the process is oxygen.

(d) Ratio of ammonia and air is 1:10.

(e) Quartz is acid resistant and when packed in layers help in dissolving nitrogen dioxide uniformly in water.

(i) The forces which are applied from a distance, without actually touching the body are called non-contact forces. 

(ii) As distance of separation increases, magnitude of non-contact force decreases.

(i) 1 kgf is the force with which earth pulls an object of mass 1 kg towards itself. 

(ii) 1 kgf = 9.8 N.

(i) Electron gun 

(ii) Deflecting system 

(iii) Fluorescent screen

Advantage of a.c. over d.c. is that it is able to travel long distance without much power loss.

 Delay and decay method is the effective way for the safe disposal of nuclear waste.

(i) (1) An electric shock may be caused either due to poor insulation of wires. (2) When the electric appliances are touched with wet hands. 

(ii) For prevent, the insulation of wires must be of good quality and it should be checked from time to time particularly when they become old, so that no wire is left naked.

(1) When the live wire comes in contact with the wet hand of the user. 

(2) Due to short circuit in the electrical gadget.

(i) Radioactivity: It is a nuclear phenomenon. It is the process of spontaneous emission of α or β and γ radiations from the nuclei of atoms during their decay. 

(ii) Nuclear Waste: The radioactive material after its use is known as nuclear waste. 

(iii) The nuclear waste obtained from laboratories, hospitals etc. must be first kept in thick casks and then they must be buried in the specially constructed deep underground stores.

 After disintegration, the radioactive material finally converts into lead and still it holds some radioactivity. This is called nuclear waste.

 Earthing can prevent a person from electric shock.

Radioactivity: The process of spontaneous emission of α, β and γ radiations from the nuclei of atoms during their decay is known as radioactivity.

Operating surplus = Rent + Interest + Profit = 90 + 100 + 220 = 410 National Income = Government final consumption expenditure + Private final consumption expenditure + Net domestic capital formation + Net exports + Net factor income earned from abroad

National Income = 800 + 900 + 200 + (- 25) + (-110) = 1900+ (-135) = 1765

F₉ – 1s²2s²2p⁵

Cl₁₇ – 1s²2s²2p⁶3s²3p⁵

(1) This is because in fluorine there is strong electron- electron repulsion for the incoming electron due to the relative compact size of 2p-orbitals in fluorine as compared to 3p-orbitals in chlorine.

(2) This is because of in red phosphorus, there are strong covalent bonds in P₄ molecules but in white phosphorus, there are Van der waals forces of attraction in P₄ molecules.

(3) This is because O₃ molecules readily dissociates to give naseent oxygen which oxidises other substances. O₃ → O₂ + [O] Nascent oxygen

Ploughing back of profits from the company’s point of view offers the following benefits: 

• It is the most convenient and economical method of finance, no legal formalities are involved and no negotiations are to be made. No return is to be paid on retained earnings and no fixed obligations are created.

• The financial structure of the company remains fully flexible. No charge is created against the assets and no restrictions are put on the freedom of management to raise further finance by floating new securities in the market. 

• Ploughing back of profits adds to the financial strength and creditworthiness of the company. A company with large reserves can face unforeseen contingencies and trade cycles with ease and economy. 

• Retained earnings can be used to redeem debts and to replace obsolete assets. A company with large reserves can take advantage of business opportunities.

The metals placed higher in the activity series (i.e. Na and K) are stable to heat and soluble in water.

Whereas metals like Ca, Mg, Al, Zn, Fe, Pb, Cu decompose on heating with decreasing vigour to form metal oxide and carbon dioxide.

The metals which lie below in the activity series (i.e. Hg, Ag) decompose on heating to form metal, oxygen and carbon dioxide.

Methods of appointment of Directors: 

The appointment of Directors may be made in the following manner: 

(i) Appointment of first Directors by promoters of the company [Section 254]: The first Directors of the company are usually appointed by the promoters. Otherwise, the signatories to the Memorandum are deemed to be the Directors, till the first Directors are elected at the first annual general meeting.

(ii) Appointment of Directors by shareholders at the annual general meeting [Section 255]: Subsequent appointment of Directors is made by the shareholders at the annual general meetings. In case of a public company and a subsidiary private company, two-thirds of the total number of Directors must be appointed by the company at the annual general meeting. At every annual general meeting, one-third of the elected Directors shall retire by rotation. The retiring Directors may be reappointed.

(iii) Appointment of Directors by the Central Government [Section 408]: The Central Gov eminent may appoint some Directors for a period of not more than three years, in the case of mismanagement of company affairs.

The duties of Directors depends upon the nature and size of the company. It is necessary for the Directors to carefully examine the Articles of the company before exercising the powers and performing their duties. 

Statutory Duties:

• Disclosure of relevant facts: It is the duty of the Directors to see that the prospectus issued by the company makes disclosure of all relevant facts and figures. 

• Holding qualification shares: It is the duty of the elected Directors to purchase qualification shares and to hold them. 

• Attending Board meeting: It is the duty of the Directors to attend Board meetings regularly in the best interest of the company. 

• Getting permission for loans from the Central Government: It is the duty of the Directors to get permission from the Central Government while taking loans from the company.