Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

4 g of NaOH is dissolved is 250 ml of a solution, the molarity of the solution will be(a) 1.0(b) 0.4(c) 2.0(d) 0.05 

Answer»

4 g of NaOH is dissolved is 250 ml of a solution, the molarity of the solution will be  0.4

2.

Why vapour pressure of a liquid decreases when a non`-` volatile solute is added to it ?

Answer» In the solution of volatile solvent and non`-` volatile solute some molecules of solute replace the solvent molecules from the surface of the solution.
3.

When and why is molality preferred over molarity in handling solution in CHMemistry?

Answer» Molarity is preferred when studies are made independent of temperature. This is because molality involves masses whiCHM do not CHMange with temperature.
4.

Which one of the following is an alkaline earth element?(a) Carbon(b) Sodium(c) Zinc(d) None of these

Answer»

Answer (d) None of these

none of these
5.

Determine the amount of `CaCl_(2)` (i = 2.47) dissolved in 2.5 L of water sucjh that its osmotic pressure is 0.75 atm at `27^(@)C`.

Answer» Correct Answer - `W_(2)=3.42g`
`Mw` of `CaCl_(2)=40+2xx35.5=111.0 g mol^(-1)`
`pi=iMRT=ixx(n)/(V)RT`
`(or)`
`n=(pixxV)/(ixxRxxT)=(0.75atmxx2.5L)/(2.47xx0.0821LatmK^(-1)mol^(-1)xx300K)`
`=0.0308mol`
`:.` Weight of `CaCl_(2)` dissolved `=nxxMw`
` =0.0308xx111.0g`
`3.42g`
6.

Explain in which of following compounds, the chemical bond would have less ionic character:LiCl or KCl

Answer»

LiCl is less than ionic character then KCl.

LiCl is the answer
7.

What is activating energy? Establish the relation between rate constant of a reaction and activation energy.

Answer»

The excess amount of supplied energy to the reactants in which the reactant contain normal energy state is equal called activation energy.

Activation energy = Threshold energy - Normal energy of reactants.

8.

Discuss briefly the structure of CaCl.

Answer»

Tetrahedral the structure of CaCl.

linear structure
9.

How is molarity of a solution different from molality.

Answer»
MolarityMolality
(i) It is total no of moles of solute dissolved in one litre of its solution.It is total no of moles of solute dissolve in per kg of solvent.
(ii) Unit = mol/litreUnit = mol/kg
10.

Isotonic solutions have same(a) Malar concentration(b) Malality(c) Normality(d) None of these

Answer»

Isotonic solutions have same Malar concentration

11.

Write any two factors which affects the conductance of electrolysis. 

Answer»

Factors which affects the conductance of electrolysis are 

(i)  the nature of the electrolyte added

(ii)  size of the ions produced and their sovation 

12.

Which of the halide of group 14 does not exist? (a) CF4 (b) Cl4 (c) SiF4 (d) Pbl4

Answer»

Pbl4 halide of group 14 does not exist.

13.

The osmotic pressure of a 1 M solution at 27°C is-(a) 2.46 atm(b) 24.6 atm(c) 1.21atm(d) 12.1atm

Answer»

The osmotic pressure of a 1 M solution at 27°C is 24.6 atm

14.

Which of the following cannot be prepared by Wurtz reaction? (a) CH4(b) C2H6 (c) C3H8 (d) C4H8

Answer»

CH4 cannot be prepared by Wurtz reaction.

15.

The cyclic polymerization of propane produces .......

Answer»

1, 3, 5-trimethylbenzene

16.

The reaction(a) Hydration (b) Dehydration (c) Dehydrogenation (d) Dehalogenation

Answer»

(b) Dehydration

17.

A group two element `M` forms a carbide which is actually a methanide (i.e., it gives off methane of hydrolysis). Then, which of the following statements is/are correct for the element?A. The aqua complex of `M^(2+)` acidic.B. Dolomite is an important mineral of the element M.C. `M` is toxic.D. `M(OH)_(@)` is amphoteric and dissolves in excess `NaOH` to form hexahydroxido complex.

Answer» Correct Answer - A::D
Be ( like Al) is the only element of group two which forms methanide, other group two elements from ethynide and allylide.
`Be_(2)C+H_(2)OtoBe(OH)_(2)+CH_(4)`
Aqua complex of `Be^(2+)` is acidic due to hydrolysis. Be (like Ba) is toxic,its hydroxide is amphoteric, but it forms only tetrahydroxido complex. Dolomite is `CaCO_(3).MgCO_(3)`
18.

Reaction between sodium ethoxide and bromoethane yieldsA. EthaneB. Ethyl alcoholC. Ethoxy ethaneD. Methoxy ethane

Answer» Correct Answer - C
19.

Say TRUE or FALSE.Calcium carbide on hydrolysis gives ethylene.

Answer»

False Calcium carbide on hydrolysis gives ethylene.

20.

Give the name of the metalloid in group 16.

Answer» Correct Answer - Tellurium.
21.

Name the radioactive chalcogen.

Answer» Radioactive chalcogen: Polonium
22.

Write the domain of f(x) = cos-1 x.

Answer»

The domain of cos-1x is [-1, 1]

23.

If a line makes angle 90°, 60° and 30° with positive direction of x, y and z axis respectively. Find its direction cosines.

Answer»

The Direction cosines are given by

=(cos90°, cos60°, cos30°)

= (0, 1/2, √3/2 )

24.

Define a Unit vector.

Answer»

A vector having Unit magnitude along any vector a is Called a unit vector in the direction of vector a add is denoted vector a|a = 1

25.

Evaluate ∫(2x - 3 cos x + ex).dx

Answer»

=> ∫(2x – 3cosx +ex).dx 

= ∫ 2 x.dx – 3 ∫ cos x.dx + ∫ ex .dx 

= 2x x2/2 - 3 x sinx + e + c 

= x2 - 3sin x + ex + c

26.

Find dy/dx if y = cos(1 - x)

Answer»

y = cos(1 - x) 

Diff w.rl.x

dy/dx = d/dx = cox(1 - x)

= -sin(1 - x) x d/dx (1 - x) dx 

= -sin(1 - x)x - 1 = sin(1 - x)

27.

The corresponding sides of two similar triangles are in the ratio 2:3, if the area of the smaller triangle is 48 cm2 , find the area of the larger triangle.

Answer»

We know that the ratio of area of two similar triangle is the square of the ratio of corresponding sides of these similar triangles. 

Let the area of the larger triangle is A cm2

Given that the area of the smaller triangle is 48 cm2 and their corresponding sides are in the ratio 2 : 3.

Therefore, \(\frac{48}{A} = (\frac{2}{3})^2\) (The ratio of Area of similar triangles is the square of the ratio of their corresponding sides.) 

⇒ A = 48 × \((\frac{3}{2})^2\) 

⇒ A = 48 × \(\frac{9}{4}\) = 12 × 9 = 108.

Hence, the area of the larger triangle is 108 cm2.

28.

`(1+x)^(n)=C_(0)+C_(1)x+C_(2)x^(2)+….+C_(n)x^(n)` then `C_(0)C_(2)+C_(1)C_(3)+C_(2)C_(4)+…..+C_(n-2)C_(n)` is equal to :A. `.^(2n)C_(n-1)`B. `.^(n)C_(n-1)`C. `.^(2n)C_(n+1)`D. `.^(n)C_(n+1)`

Answer» Correct Answer - A
29.

State the reason for the following binary operation *, defined on the set Z of integers, to be not commutative.a * b = ab3

Answer»

Let a, b ∈ Z, where Z is set of integers.

Given binary operation is a ∗ b = ab3 .

Now, b ∗ a = ba3 ≠ ab3 = a ∗ b. ( \(\because\) ba3 ≠ ab3 , where a and b are arbitrary integers )

Therefore, b ∗ a ≠ a ∗ b.

Therefore, the binary operation ‘∗’ is not commutative.

30.

A Relation R on A = {1,2,3} defined by R = {(1,1) (1,2) (3,3)} is not symmetric, Why?

Answer»

The Relation R is defined by R = {(1,1) (1,2) (3,3)} for Symmetric 

Relation if (1, 2) ∈ R then (2,1) ∈ R but (2,1) ∉ R? 

∴ R is not Symmetric Relation.

31.

Find the equation of the straight lines passing through the origin making an angle `alpha` with the straight line `y=mx+c`.A. `(y-y_(1)) = tan (theta - alpha) (x - x_(1))`, where `tan theta = m`B. `(y-y_(1)) = tan (theta + alpha) (x - x_(1))`, where `tan theta = m`C. `(y-y_(1)) = tan (theta - alpha) (x + x_(1))`, where `tan theta = m`D. `(y-y_(1)) = tan (theta + alpha) (x + x_(1))`, where `tan theta = m`

Answer» Correct Answer - A
32.

Find all the points of discontinuity on f defined by f(x) =|x| – |x + 1|

Answer»

f(x) = |x| – |x+1| 

f(c)= |c | – |c+1| 

Let c = 0, f(0) = |0 |-|1| = 0-1= -1 

Lt f(x) = It|x| – |x + 1|= |c| – |c+1| 

x→ c X → C 

let c = 0, Lt f(x)=0 – 1 = -1 

x— +0 

∴ Lt (x→0) f(x) = f(0) = -1 

⇒ f is continuous at x =0 

There is no point of Discontinuity.

33.

Let * be a binary operation defined on the set of Rational numbers Q defined by a*b = ab + 1 prove that * is a commutative.

Answer»

If * be a commutative binary operation.

a*b = b*a 

⇒ a*b = ab + 1 = ba + 1= b*a 

∴ * is commutative binary operation on*.

34.

Find the orthocenter of the triangle formed by the lines 7x + y – 10 = 0, x – 2y + 5 = 0, x + y + 2 = 0.

Answer»

Given lines are 7x + y – 10 = 0 → (1), x – 2y + 5 = 0 → (2), x + y + 2 = 0 → (3) 

Point of intersection of (2) and (3) is B (–3, 1). 

Equation of the altitude through B is (x + 3) – 7(y – 1) = 0 

⇒ x – 7y + 10 = 0 → (4) 

Point of intersection of (3) and (1) is C(2, –4) 

Equation of the altitude through C is 2(x – 2) + (y + 4) = 0 

⇒ 2x + y = 0 → (5)

Solving (4) and (5), orthocenter is (- 2/3, 4/3).

35.

Find the coefficient of `x^(-2)` in `(1+x^(2)+x^(4)) (1-1/(x^(2)))^(18)`

Answer» Correct Answer - `-681`
36.

Prove that `sin^(-1)(8/(17))+sin^(-1)(3/5)=cos^(-1)((36)/(85))`

Answer» Here, we will use,
`sin^-1x+sin^-1y = sin^-1(xsqrt(1-y^2)+ysqrt(1-x^2))`
`L.H.S. = sin^-1(8/17)+sin^-1(3/5)`
`=sin^-1(8/17sqrt(1-(3/5)^2)+3/5sqrt(1-(8/17)^2))`
`=sin^-1(8/17(4/5)+3/5(15/17))`
`=sin^-1(32/85+45/85)`
`=sin^-1(77/85)`
`=cos^-1(sqrt(1-(77/85)^2))`
`=cos^-1(sqrt(1296/7225))`
`=cos^-1(36/85) = R.H.S.`
37.

Find the middle term in the expansion of : `(1+3x+3x^2+x^3)^(2n)`

Answer» Correct Answer - `.^(6n)C_(3n) . x^(3n)`
38.

Find the last digit of the number `(13)^(12)`.

Answer» Correct Answer - 1
39.

Find the numerically greatest term in the expansion of `(2+5x)^(21)` when `x = 2/5`.

Answer» Correct Answer - `T_(11) = T_(12) = .^(21)C_(10) 2^(21)`
40.

The sum of the all rational terms in the expansion of `(3^(1//7) + 5^(1//2))^(14)` isA. `3^(2)`B. `3^(2) + 5^(7)`C. `3^(7) + 5^(2)`D. `5^(7)`

Answer» Correct Answer - A
41.

If `A, B and C` are mutually exclusive independent and exhaustive events then what is the probability that they occur simultaneously?

Answer» As given that, `A nn B nn C = O/`
and, `A nn B = O/`
`B nn C = O/`
`A nn C = O/`
and, `A uu B uu C = S`
So, the probability of occuring them simultaneously must be 0.
42.

The number of even numbers greater than 300 can be formed with the digits `1, 2, 3, 4, 5` without repetion is

Answer» Number of 3 digit numbers=>`3xx3`(when ending with 2)+`2xx3`(when ending with 4)=`15`
Number of 4 digit numbers=>`2xx3xx4xx2=48`
number of 5 digit numbers=>`1xx2xx3xx4xx2=48`
note for even numbers last digit can be occupied with 2 or 4.
total number of numbers=>`15+48+48=111`
43.

If `a,b` are the position vectors of `A,B` respectively and `C` is a point on `AB` produced such that `AC=3AB` then the position vector of `C` is

Answer» We have =>AC=3AB.
=>c-a=3b-3a
=>c=3b-2a
44.

The domain of the function f : R → R defined by \(f(x)=\sqrt{x^2 - 3x + 2}\) is:1. (-∞, 1] ∪ [2, ∞) 2. (-∞, 1) ∪ (2, ∞)3. (-∞, -3) ∪ (3, ∞)4. (-∞, -3] ∪ [3, ∞)

Answer» Correct Answer - Option 1 : (-∞, 1] ∪ [2, 

Concept:

We know that the domain of a function f(x) is the set of all values for which the function is defined, and the range of the function is the set of all values that f takes. 

Given:

\(f\left( x \right) = \sqrt {{x^2} - 3x + 2} \)

Analysis:

For domain,

f(x) ≥ 0

\(\sqrt {{x^2} - 3x + 2} \ge 0\)

(x - 2) (x - 1) ≥ 0

Case: 1

(x - 2) ≥ 0 and (x – 1) ≥ 0

x ≥ 2 and x ≥ 1

overall: x ≥ 2

{x|2 ≤ x < ∞} = [2, ∞)

Case: 2

(x - 2) ≤ 0 and (x - 1) ≤ 0

x ≤ 2 and x ≤ 1

overall : x ≤ 1

{x|-∞ < x ≤ 1} = (-∞, 1]

The domain of the function is:

(-∞, 1] [2, ∞)

45.

If 2 is root of the equation 2x2 + x2 – 13x + 6 = 0, then the equation is exactly divisible by the factor1. x - 22. 2x3. x + 64. None of the above.

Answer» Correct Answer - Option 4 : None of the above.

Concept:

If the root is 2, it means that the polynomial is completely divisible by x - 2.

The given polynomial looking carefully is 3x2 – 13x + 6 = 0 and it does not have any root equal to 2.

The correct answer is not available in the options given in the exam and hence one of the options has been modified. 

46.

The order of acidic strength for the following compounds is `:-` A. `igtiigtiii`B. `iigtiiigti`C. `igtiiigtii`D. `iiigtigtii`

Answer» Correct Answer - A
47.

Which of the following is not a valid resonance structure of the others?A. B. C. D.

Answer» Correct Answer - D
48.

Which of the following is most stable confirmational isomer `:-`A. B. C. D.

Answer» Correct Answer - A
49.

Which of the following expected to have `100%` enolic form?A. B. C. D.

Answer» Correct Answer - C
50.

are related to each other form?A. Functional IsomersB. Ring-chain IsomersC. Position IsomersD. Both (1) and (2)

Answer» Correct Answer - D