Explore topic-wise InterviewSolutions in Current Affairs.

Correct Answer is: (A) Dibasic acid 

Sulphuric Acid, H₂SO₄, is a dibasic acid in nature as it contains 2 hydrogen atoms which ionise in aqueous solution to become Hydrogen Ions.

The S.I. unit of Density is Kg m^-3.

The number of moles of solute dissolved in 1 kg of the solution.

A decinormal solution is the solution containing 0.1 g equivalent (1/10^th) of solute / substance dissolved in 1 dm³ of solution.

The atomic mass of an element which exists as mixture of two or more isotopes is the average of atomic masses of its isotopes. This is called average atomic mass.

Average atomic mass is the average of atomic mass of all the isotopes of an element.

Correct Answer is: (B) Ostwald process 

The Ostwald process converts ammonia to nitric acid and involves two steps:

• In step 1, ammonia is oxidized to form nitric oxide and also nitrogen dioxide. 

• In step 2, the nitrogen dioxide that was formed is absorbed in water. This in-turn forms nitric acid. 

i. Molecular mass of H₂O = (2 × Average atomic mass of H) + (1 × Average atomic mass of O)

= (2 × 1.0u) + (1 × 16.0 u)

= 18 u

ii. Molecular mass of C₆H₅Cl = (6 × Average atomic mass of C) + (5 × Average atomic mass of H) + (1 × Average atomic mass of Cl) 

= (6 × 12.0 u) + (5 × 1.0 u) + (1 × 35.5 u) 

= 112.5 u

iii. Molecular mass of H₂SO₄ = (2 × Average atomic mass of H) + (1 × Average atomic mass of S) + (4 × Average atomic mass of O) 

= (2 × 1.0 u) + (1 × 32.0 u) + (1 × 16.0 u) 

= 98 u

∴ i. The molecular mass of H₂O = 18 u

ii. The molecular mass of C₆H₅Cl = 112.5 u

iii. The molecular mass of H₂SO₄ = 98 u

Mole Fraction is the ratio of number of moles of one component to the total number of moles (solute and solvents) present in the solution. It is expressed a.s 'x'.

A solution containing 1 gm equivalent of the substance dissolved in 1 dm³ of the solution.

Average atomic mass is the average of atomic mass of all the isotopes of an element. 

The ratio of number of moles of a component to the number of moles present in the solution.

One a.m.u. or u is equal to 1/12th of the mass of an atom of carbon -12. 

One a.m.u. or u is equal to 1/12^th of the mass of an atom of carbon -12.

The SI unit of mass is kilogram. It is equal to the international prototype of the kilogram.

The SI unit of mass is kilogram. It is equal to the international prototype of the kilogram.  

Because a correct chemical equation must be in accordance with the law of conservation of mass according to which the total mass of the reactants must be equal to the total mass of the product.

1.992648 × 10^–23 g ≈ 1.99 × 10^–23 g

(a) mol L^-1 (b) mol Kg^-1 (c) No units.

Molarity = Number of moles of solute/Volume of solution in litres

Molality = Number of moles of solute/mass of solvent in kg

Symbol for SI Unit of mole is mol.

One mole is defined as the amount of a substance that contains as many particles or entities as there are atoms in exactly 12 g (0.012 kg) of the ¹²C isotope.

(i), (iv)

(i) Law of conservation of mass

(iv) Avogadro law

(i), (iv). Statements (i) and (iv) involve masses and volume, respectively. Therefore, these are not related to the statements. 

Correct option is d. 50 g of magnesium oxide and 10 g of oxygen

Molality is the number of moles of solute present in one kilogram of solvent but molarity is the number of moles of solute dissolved in one litre of solution. 

Molality is independent of temperature whereas molarity depends on temperature.

1. 24

2. hydrogen

3. good conductor

4. acidic

That temperature at which solid changes into liquid state is called melting point of that object. Due to hardness of solid their melting point is high such as iron (Fe). The melting point of iron is 1593°C while galium is exception it melts just by putting it on hand palm as its meting point is very low.

When some amount of metal or non metal is mixed with main metal, then it is called mixed metal or alloy, for examples – in stainless steel chromium and nickel is mixed to protect it from rusting. In brass, zinc and copper are mixed in a fixed quantity to get desired properties such proportionate mixture is called an alloy such as bronze, brass and stainless steel.

Metals are spread on beating by the force of a hammer. They are converted into sheets. This property is known as malleability.

The metal found in liquid state is Mercury.

(a) Aluminium and copper.

(b) Copper and aluminium.

(c) Gold and silver.

Diet provides iodine for making thyroxine hormone which keeps the thyroid gland healthy.

The property of metal by which it can be drawn into wires is called Ductility.

Aluminium foil.

(a) Thyroid gland.

(b) Salivary glands.

(c) Pancreas.

The property of metals by which they can be beaten into thin sheets is called Malleability.

(a) Hydrogen.

(b) Hydrogen.

(c) Carbon.

(d) Nitrogen.

(e) Sulphur.

Correct answer is (b) Venus 

Feedback mechanism.

Metal which does not react even with steam Silver.

(a) Metals are malleable.

(b) Non-metals are non-malleable.

Nitrogen, Oxygen, Chlorine, Argon

C) 1 – c, 2 – d, 3 – b, 4 – e, 5 – a

Ethanol and Ethanoic acid are important carbon compounds in our daily life.

Aluminium is used for making cooking coil as it is very light weight metal, resistant to corrosion and is good conductor of heat.

Brittleness is the property of being brittle i.e. breaking easily.

Non-metals show brittleness.

The importance of carbon compounds in our daily life

• Foods [starch, sugar, fats, vitamins, proteins]

• Fuels [wood, coal, alcohol, petrol]

• Household and commercial articles [paper, soap, cosmetics, oils, paints]

• Textile fabrics [cotton, wool, silk, linen, rayon, nylon]

• Drugs and disinfectants [penicillin, quinine, aspirin, sulpha drugs]

• Poisons [opium, strychnine]

• Perfumes [vanillin, camphor]

• Explosives [nitro glycerine, dynamite, picric acid, TNT]

• Dyes [indigo, congo red, malachite green]

• War gases [mustard gas, chloropicrin, lewisite]

Correct option is C) mercury