Chemistry

1.The mineral containing both magnesium and calcium is

magnesite calcite carnallite dolomite

2.The most extensive, commercially useful source of thorium as monazite sand occurs in India at

Orissa coast Travancore coast West Bengal coast Gujarat coast

3.The main active constituent of tea and coffee is

nicotine chlorophyll caffeine aspirin

4.The hardest form of carbon is

coke graphite diamond charcoal

5.The hottest part of the gas flame is known as

luminous zone dark zone blue zone non-luminous zone

Chemistry

1.The gas used for artificial ripening of green fruit is

ethylene ethane carbon dioxide acetylene

2.Zone refining is used for the purification of

Au Ge Ag Cu

3.The main chemical constituent of the oil of cardamom which is responsible for flavour of this oil is

cineole engenol geraniol limonene

4.The high reactivity of fluorine is due to

its high electro negativity small size of fluorine atom availability of d-orbitals strong F - F bond

5.The major constituent of air is

nitrogen carbon dioxide oxygen hydrogen

Chemistry

1.The oldest rocks in the earth's crust were once molten, and came from deep inside the earth. The molten rock, called magma, spewed out in volcanic eruptions during the earth;s early life and solidified into hard rock's called

granite basalt igneous rocks sedimentary rocks

2.The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is

Dalton's law Gay Lussac's law Henry's law Raoult's law

3. The gas present in the stratosphere which filters out some of the sun's ultraviolet light and provides an effective shield against radiation damage to living things is

helium ozone oxygen methane

4.The most commonly used bleaching agent is

alcohol carbon dioxide chlorine sodium chlorine

5.The heat required to raise the temperature of body by 1 K is called

specific heat thermal capacity water equivalent None of the above

Chemistry

1.The nucleus of an atom consists of

electrons and neutrons electrons and protons protons and neutrons All of the above

2.The number of moles of solute present in 1 kg of a solvent is called its

molality molarity normality formality

3.The most electronegative element among the following is

sodium bromine fluorine oxygen

4.The metal used to recover copper from a solution of copper sulphate is

Na Ag Hg Fe

5.The metallurgical process in which a metal is obtained in a fused state is called

smelting roasting calcinations froth floatation