Consider the following statements:
If there were no phenomenon of capillarity
1. It would be difficult to use a kerosene lamp.
2. One would not be able to use a straw to consume a soft drink.
3. the blotting paper would fail to function.
4. the big trees that we see around would not have grown on the earth.
Which of the statements given above are correct?
Biogas mainly consists of
Acid rains is caused due to emission of which of the following into the atmosphere?
Helium is preferred to hydrogen in air balloons because it
Hydrofluoric acid is not kept in glass bottles because it reacts with
The inexhaustible source of energy of the stars is due to
Consider the following statements:
Assertion (A): LPG is a pollution free vehicular fuel.
Reason (R): Plying of CNG fuelled-buses is recommended for metropolitan cities in India.
Domestic cooking gas consists of mostly
Consider the following parts of spectra:
1. Visible 2. Infrared 3. Ultraviolet 4. Microwave
Which of the following is the correct sequence in which the wavelengths increase?
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The blue colour of water in the sea. What is the reason behind the phenomenon?
When soggy biscuits are kept inside the fridge for sometime they become crisp because
Which one of the following pairs is correctly matched?
In the process of electroplating a utensil with zinc,
What is “ Kiss of death” ?
Consider the following statements: Hard water is not suitable for
1. Drinking
2. Washing clothes with soap
3. Use in boilers
4. Irrigating crops
Which of these statements are correct?
What is the role of ultraviolet (UV) radiation in the water purification system?
1. It inactivates / kills the harmful micro- organisms in water.
2. It removes all the undesirable odours from the water.
3. It quickens the sedimentation of solid particles and improves the clarity of water.
Which of the statements given above is/are correct?
In cold weather, aquatic animals survive even when water to the top layer of the lake freezes into ice because
Hydrogen bomb is based on the principle of
The difference between a nuclear reactor and atomic bomb is that
The order of appearance of the following with increasing temperature during the refining of crude oil is
A sample of chloroform before using as an anaesthetic, is tested by
While tinning of brass utensils, the ammonium chloride powder used to clean the hot utensil produces fumes of
Which one of the following is not correct?
Living in the atmosphere of CO is dangerous because it