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Lithium is the strongest reducing agent though it has the highest ionization energy in its group. Which of the following factors is responsible for making Li the strongest reducing agent (a) Large heat of atomisation (b) Smaller size (c) Large sublimation energy (d) Large amount of hydration enthalpy

Large amount of hydration enthalpy Lithium ion is smaller in size. Hence, it can attract large number of water molecules. Several water molecules... View Article

The involuntary actions in the body are controlled by (a) spinal cord (b) cerebellum (c) medulla in forebrain (d) medulla in hindbrain

The involuntary actions in the body are controlled by medulla in hindbrain Involuntary action is the set of muscle movement which do not require... View Article

What happens in the Putting-out system?

For the weavers, this arrangement has two advantages: 1. The weavers do not have to spend their money on the purchase of yarn. 2. Weavers... View Article

Find the difference between the place value and the face value of the digit 6 in 72601

Given number = 72601 Here, Face value of 6 = 6 Place value of 6 = 600 Difference between place value and face value = 600 - 6 We get, = 594... View Article

Which of the following is medicinal plant? (a) dalbergia (b) linum (c) aconitum (d) tectona

Aconitum Aconitum has long been used in Ayurveda and traditional Chinese medicine. In case of tonsillitis, aconitum seeds are crushed and mixed... View Article

In the fruit of pomegranate the edible part is (a) Juicy epicarp (b) Juicy testa (c) Pulpy mesocarp (d) Placental hair

The edible part in the fruit of pomegranate is juicy testa Hence, the correct option is (b)... View Article

Elements of group 14 exhibit oxidation sate of: (a) +4 only (b) +2 and +4 only (c) +1 and +3 only (d) +2 only

Group 14 elements possess 4 valence electrons. Consequently, group oxidation status is + 4. However, the lower oxidation state becomes... View Article

Name the cell organelles concerned with trapping of solar energy

Plastids, in particular, the Chloroplasts are responsible to trap solar energy for the process of photosynthesis as they contain the green... View Article

Meter bridge works on the principle of

A meter bridge also called a slide wire bridge is an instrument that works on the principle of a Wheatstone bridge. A meter bridge is used in... View Article

Albuminous cells occur in (a) Xylem (b) Phloem (c) Sclerenchyma (d) Collenchyma

Phloem The key element of Phloem is the sieve component and the companion cell. The sieve element is known as the sieve tube in angiosperms, and... View Article

What is the correct sequence of different phases of cell cycle?

The cell cycle comprises two phases, i.e. interphase and mitosis or M phase. Interphase is further divided into three phases, G1, S and G2. Hence... View Article

A block of mass 10kg is moving in x direction with a constant speed of 10 m/s. It is subjected to a retarding force F = -0.1 x J/m during its travel from x = 20 m to x = 30 m. Its final kinetic energy will be: (a) 475 J (b) 450 J (c) 275 J (d) 250 J

Applying work energy theorem W = (KE)f - (KE)i On calculation, we get, (KE)i = 500 J We get, W = -25 J W = (KE)f - (KE)i Substituting... View Article

The boiling point of 0.2 mol kg^-1 solution of x in water is greater than equimolal solution of y in water. Which of the following statement is true in this case? (a) molecular mass of x is less than the molecular mass of y (b) y is undergoing dissociation in water while x undergoes no change (c) x is undergoing dissociation in water (d) molecular mass of x is greater than the molecular mass of y

We have, (ΔTb)x > (ΔTb)y Same solvent. Hence Kb is same Given that m is same ix.kb.m > iy.kb.m ⇒ ix > iy Therefore, x... View Article

Expansion of (2a + 3b + 4c)^2 is ___________ (a) 4a^2 + 9b^2 + 16c^2 + 12ab + 24bc + 16ca (b) a^2 + b^2 + 2ca (c) a^2 – b^2 – 2ca (d) a^2 – b^2 + 2ca

We know (x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx Here, x = 2a y = 3b z = 4c Substituting the values in the above formula, we get, ⇒ (2a... View Article

A fruit seller buys lemons at 2 for a rupee and sells them at 5 for three rupees. What is his profit? (a) 15% (b) 20% (c) 10% (d) 25%

Cost price of one lemon = Rs 1/2 = 0.5 Selling price of one lemon = Rs 3/5 = 0.6 Profit (%) = On calculation, we get, ⇒ 20%... View Article

On heating a mixture of NH4Cl and KNO2 we get: (a) NH4NO3 (b) KNH4(NO3)2 (c) N2 (d) NO

On heating a mixture NH4Cl and KNO2 we get nitrogen gas, potassium chloride and two moles of water. The reaction in which heating a mixture NH4Cl... View Article

Which of the following performs modulation and demodulation? (a) Coaxial cable (b) Satellite (c) Modem (d) Optical fibre (e) None of these

A modem performs both modulation and demodulation. A modem is a hardware which connects to a computer, broadband network or wireless router.... View Article

The density of a cube is measured by measuring its mass and the length of sides. If the maximum error in the measurements of mass and length are 4% and 3% respectively, the maximum error in the measurement of density will be (a) 7% (b) 9% (c) 12% (d) 13%

mass of the cube = m length of the side of the cube = a volume of the cube v = a3 Density of the cube = ρ ρ = (m/v) = (m/a3) Since, error... View Article

An express train is moving with a velocity v1. Its driver finds another train is moving on the same track in the same direction with velocity v2. To escape collision driver applies a retardation a on the train. The minimum time of escaping collision be (a) t = (v1 – v2)/a (b) t = (v1^2 – v2^2)2 (c) None (d) Both

Given Both the trains are moving in the same direction. We will first calculate the relative velocity between them Initial relative velocity will... View Article

A charge q1 exerts some force on a second charge q2. If a third charge q3 is bought near, the force of q1 exerted on q2: (a) decreases (b) increases (c) remains unchanged (d) increases if q3 is of same sign as q1 and decreases if q3 is of opposite sign

remains unchanged As per the principle of superposition, The force between any two charged particles is independent of all other charges in the... View Article