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For the redox reaction, MnO-4 + C2O2-4 + H+ → Mn2+ + CO2 + H2O. What will be the correct coefficients of the reactants for the balanced equation?

(A) MnO-4 = 2,C2O2-4 = 16, H+ = 5 (B) MnO-4 = 2,C2O2-4 = 5, H+ = 16 (C) MnO-4 = 16,C2O2-4 = 5, H+ = 2 (D) MnO-4 = 5,C2O2-4 = 16, H+ = 2... View Article

An organic compound made of C, H and N contains 20% nitrogen. Its molecular weight will be:

(A) 65 (B) 70 (C) 100 (D) 140 The Correct Answer is (B) 70 Solution: The Atomic mass of nitrogen is 14. As given, the compound... View Article

Assertion: soft drinks and soda water bottles are sealed under high pressure. Reason: High pressure maintains the taste and texture of soft drinks.

(A) Assertion is true, but the reason is false. (B) Both assertion and reason are false. (C) Both assertion and reason are true. The reason is... View Article

When two liquids of the same volume but of different densities, ρ1 and ρ2 are mixed together, then the density of the mixture is

(A) (B) (C) (D) The Correct Answer is Solution: Density of the mixture = Let the first liquid have mass M1, density ρ1... View Article

A hydrocarbon C5H10 does not react with chlorine in dark but gives a single monochloro compound C5H9Cl in bright sunlight. Identify the hydrocarbon.

Solution: The molecular formula of hydrocarbons is C5H10, which satisfies the general formula CnH2n. This suggests that the hydrocarbon can... View Article

AB is a line segment and P is its mid-point. D and E are points on the same side of AB such that ∠BAD=∠ABE and ∠EPA=∠DPB. Show that (i) △DAP≅△EBP (ii) AD=DE

i) △DAP≅△EBP Given that, ∠EPA=∠DPB Now, ∠EPA+∠DPE=∠DPB+∠DPE Hence, ∠DPA=∠EPB Now, by using the triangles EBP and DAP, ∠EBP=∠DAP (given)... View Article

It is proposed to add to a square lawn with each side 58 m two circular ends the centre of each circle being the point of intersection of the diagonals of the square the area of the whole lawn is

Consider ABCD is a square lawn whose side is 58m. Also, AED and BFC are the two circular ends Therefore, the diagonal of the lawn = 58√2 m... View Article

ABC is an isosceles triangle in which AB=AC.AD bisects exterior angle QAC and CD∥BA as shown in the figure. Show that (i) ∠DAC=∠BCA (ii) ABCD is a parallelogram

(i) ∠DAC=∠BCA Since, ABC is an isosceles triangle, Let, ∠ABC=∠BCA=y Also, given that ∠QAD=∠DAC = x (Let) By using the alternate interior... View Article

If k is said to be a zero of a polynomial function P(X), if P(k) = ___.

According to the definition of zeroes of a polynomial, the real number “k” is said to be a zero of a polynomial P(x), if P(k) = 0.... View Article

Varun owns a farm which is in the shape of a scalene triangle, and its side dimensions are given. To find its area, he preferred heron’s formula. Interpret the reason for it.

Varun preferred Heron’s formula to find the area of a farm for the following reason: Since all the side lengths of a scalene triangle are given,... View Article

The least number which when divided by 6, 9, 12, 15, 18 leaves the same remainder 5 in each case, is

To find the least number which when divided by 6, 9, 12, 15, 18 leaves the same remainder 5 in each case, we have to find the LCM of 6, 9, 12,... View Article

If resultant of two vectors a and b shown in the figure is √7b. The value of b/a is

As we know, resultant vector, R2 = A2 + B2 + 2ABCos θ Thus, from the given value, We can write (√7b)2 = a2+b2+2ab Cos60° 7b2 = a2+b2+2ab(½)... View Article

If one root is square of the other root of the equation x^2+px+q=0, then find the relation between p and q.

Let α and α2 be the two roots of the equation x2+ px+q = 0. Thus, α + α2 = -p α(1+α) = -p, and α3 = q Now, (α(1+α)3 = (-p)3 α3(1+α)3 = -p3... View Article

The function f(x)=∣x∣+∣x−1∣ is continuous at

(a) f(x) is continuous at x = 0 and x = 1 (b) f(x) is continuous at x = 0, but not x = 1 (c) f(x) is continuous at x = 1, but not x = 0 (d)... View Article

The number of terms in the expansion of (a + b + c)n, where n ∈ N is

Given that, (a+b+c)n This can be written as [a+(b+c)]n =an+nC1an−1(b+c)1+nC2an−2(b+c)2+......+nCn(b+c)n On expanding each... View Article

Find the area of a parallelogram whose adjacent sides are represented by the vectors, A = 3i+j+4k,and B = i-j+k.

If the adjacent sides of a parallelogram are represented by a vector, then the formula to calculate the area of a parallelogram is |Vector A... View Article

In figure, AB ⊥ AE, BC ⊥ AB, CE = DE and ∠AED = 120°, then find ∠ECD.

Given that AEDB is a quadrilateral. We know that the sum of the interior angles of a quadrilateral is 360°. From the given figure, it is... View Article

The number of points of discontinuity of f(x)={x/5}+[x/2] in x in [0,100] is/are (where [.] denotes greatest integer function and {.} denotes fractional part function) .

Time period of fractional part of x, {x} = 1 But in the given question, we have, {x/5} Thus, the time period will be 5. To plot the graph for... View Article

If two interior opposite angles of a triangle are equal and external angle is given to be 110° , then each of the equal interior angle is ____.

As we know that the sum of two interior opposite angles of a triangle is equal to its exterior angle, x + x = 110° 2x = 110° x =... View Article

Let ABCD be a trapezium with parallel sides AB and CD such that the circle S with AB as its diameter touches CD. Further, the circle S passes through the midpoints of the diagonals AC and BD of the trapezium. The smallest angle of the trapezium is

Now, consider the figure as given below, Now, join AN, and hence ∠ANB = 90° In triangle, ANB, Cos θ = BN/2r BN = 2r cos θ Thus, BD = 2BN =... View Article

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