If we add a handful of garden soil to a beaker filled three-quarters with water, stir the contents with a stick to dissolve the soil and then let it stand undisturbed for some time, we observe different layers. The order of these layers from the bottom to the top is
gravel, clay, sand, humus, water
sand, gravel, clay, water, humus
clay, sand, gravel, humus, water
gravel, sand, clay, water, humus
Cereals such as wheat and gram are grown in an area. The soil of this area must be
loamy and sandy
clayey
sandy and clayey
clayey and loamy
When a copper plate is exposed to moist air for long, it acquires a dull green coating. The green material is
copper sulphate
a mixture of copper hydroxide and copper sulphate
a mixture of copper carbonate and copper sulphate
a mixture of copper carbonate and copper hydroxide
D.
a mixture of copper carbonate and copper hydroxide
When a copper plate is exposed to moist air for a long time, it acquires a dull green coating because copper metal reacts with carbon dioxide and moisture (water) of air to form a green coating of basic copper carbonate on the surface of the copper plate. This basic carbonate is a mixture of copper carbonate and copper hydroxide, CuCO3·Cu(OH)2 Hence, the green material on a copper plate is a mixture of copper carbonate and copper hydroxide.
In which of the following units is the calorific value of fuels generally expressed?
Calories per gram
Kilocalories per kilogram
Joules
Kilojoules per kilogram
The metamorphosis of tadpoles is not possible if the water in which they are growing does not contain sufficient
calcium
oxygen
iodine
minerals
Which of the following commonly used fuels has maximum calorific value?
Compressed Natural Gas (CNG)
Diesel
Liquefied Petroleum Gas (LPG)
Petrol
Air is a mixture of many gases. The percentage by volume, of the gases other than nitrogen and oxygen, i.e., CO2 methane, argon, ozone and water vapour combined together is about
0.1%
1%
21%
78%
Which of the following endocrine glands secretes sugar controlling hormone?
Adrenal
Pancreas
Pituitary
Thyroid
Select the one which is different from the others in the manner it is applied.
Electrostatic force
Frictional force
Gravitational force
Magnetic force
A person is suffering from a disease named 'Goitre'. Which of the following glands of the person is not functioning properly?
Adrenal
Pancreas
Pituitary
Thyroid