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In conversion from ethanol to ethene, concentrated sulphuric acid is used as:

During the conversion of ethanol into ethene in the presence of con. Sulphuric acid, a molecule of water is lost. In this reaction, con.... View Article

What is the ratio of C.G.S. to M.K.S. unit of acceleration?

C.G.S unit of acceleration = 1 cm/s2 M.K.S. unit of acceleration = 1m/s2 The ration of C.G.S. to M.K.S. unit of acceleration is = C.G.S unit of... View Article

An insulated copper wire is wound on a soft iron core. Current is passed through the coil such that at end A the current flows anti- clockwise and a magnetic compass needle placed at other end B of the coil. a) What polarity is created at B? b) How is the magnetic compass affected when current flows through the coil?

Answer: i) At end B current flows clockwise thus end B becomes the South Pole. ii) The compass needle will be directed towards the south pole at... View Article

In an experiment, Radha took small amounts of an unknown food item in a test tube. Then, she added two drops of copper sulphate solution in the test tube along with a few drops of caustic soda solution. After a few minutes, the colour of the food item changed to violet.In the given experiment, the change in colour of the food item to violet indicates the presence of

The change in colour of the food item to violet after the addition of copper sulphate and caustic soda solution indicates the presence of... View Article

Addition of ozone molecule to alkene to form ozonide is known as:

The Addition of ozone molecule to alkene to form unstable ozonide followed by reduction with zinc dust and water to form carbonyl compounds is... View Article

Why is it advised to drive along the slippery road slowly?

It is advised to drive along the slippery road slowly, because friction is reduced and if the driver is driving at a larger speed there is a risk... View Article

What is the state of an object, if the object is experiencing a net zero unbalanced force?

If an object experiences a net zero unbalanced force, then the body moves with a constant velocity, or if it was at rest, then it continues to... View Article

Which part of eye that has the highest concentration of cones?

The macula lutea or the fovea centralis, also called yellow spot has the highest concentration of cones. The image formed here is very clear and... View Article

Give examples of three physical quantities that are having dimensions [ M L-1 T-2].

Pressure = Force/Area = ML1T-2/ L2 = [M L-1 T-2] Stress = Force/Area = ML1T-2/ L2 =[M L-1 T-2] Coefficient of elasticity = Stress/strain = [M... View Article

Why do the liquids boil at lower temperature at high altitude?

At high altitudes, the atmospheric pressure is quite low as compared to that at sea level. So water boils at a lower temperature at high... View Article

How to determine the exact position and momentum of an electron?

Simultaneous determination of exact position and momentum of an electron is not possible. This is according to Heisenberg's uncertainty... View Article

Why is making of anti-viral drugs is more difficult than making anti-bacterial medicines?

Making anti-viral drugs is more difficult than making anti-bacterial medicines because viruses have very few biochemical mechanisms of their own.... View Article

Which of the following has a higher inertia: a football or a stone of the same size?

Inertia of stone is greater than the inertia of football because mass of stone is higher than the mass of football even both are of same size... View Article

Isha’s eye balls are too short due to which she cannot see

Since Isha's eye balls are short, so she is suffering from hypermetropia. In this defect, a person is not able to see the nearby objects.... View Article

Which disease is marked by inflammatory or degenerative changes of the nerves? a) Beriberi b) Rickets c) Scurvy d) Xerophthalmia

Beriberi: Impairment of the nerves and heart Rickets: Brittle bones Scurvy: Bleeding gums Xerophthalmia: Dryness of cornea and ulceration... View Article

Have you seen any other organism besides redworms in your pit? If yes, try to find out their names.

Yes. A pit might contain other soil microbes such as bacteria, other species of earthworms such as brandling worm,small bugs, flies, moulds and... View Article

Which of the following terms does not represent electrical power in a circuit? (1) I²R (2) IR² (3) VI (4)V²/R

Answer: (2) IR2 In physics, the rate of electrical energy transfer by an electrical circuit per unit time is determined by electric power. It is... View Article

How do we separate a mixture of anthracene and sodium chloride?

Anthracene sublimes on heating and gets collected on the cooler sides of the inverted funnel and sodium chloride will be left behind.... View Article

The volumes of gases A, B, C and D are in this ratio 1 : 2 : 2 : 4 under the same conditions of temperature and pressure.If the volume of A is actually 5.6 dm3 at STP, calculate the number of molecules in the actual volume of D at STP (Avogadro’s number is 6 x 10 23). The volume of D is four times the volume of A as given.

The volume of D will be 4 x 5.6 dm3 at STP = 22.4 dm3 at STP The number of molecules in the volume (22.4 dm3) of D at STP = 6 x 1023.... View Article

Which of the following is not a derivative of skin? (a) Thyroid gland (b) Sebaceous glands (c) Mammary glands (d) Sweat Glands

Answer: (a) Thyroid gland The special derivatives of human skin include the hair, nails, sebaceous glands, sweat glands and mammary glands.... View Article

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