Explore topic-wise InterviewSolutions in Current Affairs.

(c) Transmitting nerve signals

1. BeO has higher lattice enthalpy than hydration enthalpy and hence is insoluble in water. BeSO₄ on the contrary, is soluble because the lattice enthalpy is less due to bigger sulphate ion.

2. In barium oxide, BaO, due to larger size of barium ion the lattice enthalpy is less than hydration enthalpy and hence it is soluble in water. On the other hand, in BaSO₄ due to larger size of barium as well as sulphate ion, the magnitude of hydration enthalpy is much smaller than the lattice enthalpy and hence it is insoluble in water.

3. In Kl the chemical bond is ionic in character. On the other hand, due to small size of lithium ion and its high polarising power, the bond in Li is predominantly covalent in character. Hence, Li is more soluble than Kl in ethanol.

Answer: (3) Fe 

₂₆Fe = [Ar]3d⁶ 4s²

Answer is (4) Molecular orbital theory

In complex [Ni(CO)₄] decrease in Ni–C bond length and increase in C–O bond length as well as it's magnetic property is explained by MOT.

Answer is (4) Molecular orbital theory.

a. Increases the rate of forward reaction 

b. No effect 

c. Increases the rate of backward reaction

Answer: (2) C > D > B > A

E1 reaction proceeds via carbocation formation, therefore greater the stability of carbocation, faster the E1 reaction

Answer is (4)

Alanine does not show Biuret test because Biuret test is used for deduction of peptide linkage & alanine is amino acid.

Albumine is protein so have paptide linkage so it gives positive Biuret test.

Positive Barfoed test is shown by monosaccharide but not disaccharide.

Positive Molisch's test is shown by glucose.

Answer is (4)

Lactose, Glucose and Fructose give +ve motisch's test.

Glucose give +ve barfoed test and fructose give –ve barfoed test.

Albumin give the biuret test and alamine give –ve Biuret test.

So, the answer should be 2.

Answer: (4) Oxalic acid in burette and NaOH in conical flask

Oxalic acid is a primary standard solution while H₂SO₄ is a secondary standard solution. 

Answer: (4) a, c, d and e

CO₂, O₃, H₂O vapours and CFC's are green house gases.

Answer: 48.00

|W| = 1/6 (6 + 10)x 6 = 48J

Correct option (C) Both

Explanation:

Condition necessary for ionic bonds formation is 

(i) Low ionisation energy of electro positive element. 

(ii) High Electron affinity of electro negative element.

Answer : (4) [Co(NO₂)₃ (NH₃)₃]

[Ma₃b₃] type complex shows facial and meridional isomerism

Correct option (D) All the above

Explanation:

Calcination - In this process metallurgy ore is heated in the absence of air. It‟s main role are : 

(i) To remove moisture 

(ii) To decompose carbonates 

(iii) To derive of organic matter

Answer : (3) B only 

At a particular temperature as inter molecular force of attraction increases vapour pressure decreases.

Answer is (1) ρ_M > ρ_A > ρ_C

ρ_M = 98 × 10^–8 

ρ_A = 2.80 × 10^–8 

ρ_C = 1.72 × 10^–8 

ρ_T = 5.65 × 10^–8 

ρ_M > ρ_T > ρ_A > ρ_C

None of the option

Solution :

For all process

E_AB = E_AC = E_AD

W_AB > 0

W_AC = 0

W_AD < 0

None of the option matches.

(3) A-B has the stiffest bone 

From the given graph, potential energy of A-B molecule is minimum. 

Thus A-B bond is most stable and have strongest bond amongst these. 

B → Most electronegative 

D → Least electronegative 

A-B → Shortest bond length 

A-B → Largest bond enthalpy 

Therefore correct option is (3).

Correct answer is (4) 4.0 × 10¹⁸

PV = NkT

E = \(\frac{3}{2}\)kT

N = \(\frac{3PV}{2E}\) (P = hρg)

= 4 x 10¹⁸

(1) Global warming and acid rain 

Due to industrial process SO₂ gas is released which is responsible for acid rain & global warming.

Answer is (3) (B) and (C)

Mean free path is independent of temperature and relaxation time decreases as temperature increases.

(a) CaCO₃ + Δ → CaO + CO₂ {In Blast furnace} lime stone 

(b) Ag form cyanide complex [Ag(CN)₂] – during cyaride process 

Ag / Ag₂S + CN^Θ → [Ag(CN)₂]^-

(c) Ni is purified by mond's process 

(d) Zr and Ti are purified by van arkel method 

All (a), (b), (c), (d) are correct statements 

Thus correct option is (4)

Definition: The galvanometer is the device used for detecting the presence of small current and voltage or for measuring their magnitude. The galvanometer is mainly used in the bridges and potentiometer where they indicate the null deflection or zero current.

Tissue culture is a propagation method used to produce plants under sterile conditions. This method uses plant parts (Explants) that have been sterilized before being placed in suitable suspension medium to grow. 

Plant propagation through tissue culture method is called micro propagation. It is called as invitro micro propagation, because, the explants are grown on medium and the genetic resources are conserved in the form of in vitro maintained tissues. Micro propagated plants are free from viruses and show increased productivity and yield.

Answer: b) Helical structure 

Phenol can be used as an antiseptic as well as a disinfectant. 0.2% solution of phenol acts as antiseptic where as 1% solution acts as disinfectant.

Acid catalyzed hydration of alkenes except ethene leads to the formation of Secondary or tertiary alcohol 

The best reagent to convert pent-3-en-2-ol into pent-3-en-2-one is pyridinium chlorochromate 

a) Pheromones 

b) 1. attracting mates 

2. informing availability of food 

3. determining the path of travel 

4. informing the dangers

a) Pheromones 

b) To attract mates, to inform about food or dangers, to live in colonies, to follow one after the other.

c) Civetone in civet cat, Bombycol in female silkworm moth.

Due to hypothyroidism (eg. cretinism) low metabolic rate, sluggishness, sleeplessness, increase in body weight, hypertension, oedema, etc.

Due to hyperthyroidism (eg. Graves disease) high metabolic rate, increased heartbeat, rise in body temperature, sweating, sleeplessness, loss of weight, emotional imbalance.

a) Diabetes 

b) Myxoedema 

c) Osteoporosis 

d) Goiter

9-11 mg/100 ml blood.

When the level of calcium in blood increases, thyroid gland secretes a hormone named calcitonin. It lowers the level of calcium in blood by depositing excess calcium in bones and by preventing the mixing of calcium with blood form the bones. When the level of calcium in blood decreases, parathyroid gland secretes parathormone. It increases blood calcium by reabsorbing it from the kidneys and also preventing the deposition of calcium in bones.