Top 1000+ Solved Chemistry MCQ Questions Answer
Q. Water is not effective in extinguishing a fire caused by petrol because –
a. the flame is too hot for water to cool it down
b. water and petrol react chemically
c. water and petrol are miscible with each other
d. water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn
Q. "All the four quantum numbers of two electrons in an atom are not the same." It is the law of
a. Hund’s
b. Exclusion Principle of Pauli
c. Uncertainty Principle of Giesenberg
d. Avogadro’s law
Q. The three elements most needed in common fertilizers are –
a. Sulphur, Phosphorous and Sodium
b. Nitrogen, Phosphorous and Sodium
c. Phosphorous, Sodium and Nitrogen
d. Calcium, Phosphorous and Potassium
Q. Metal are good conductors, because –
a. they contain free electrons
b. the molecules in them are very close to each other
c. the molecules in them collide very freely
d. they contain reflecting surface
Q. Helium gas is filled in ballons because
a. its atomic number is 2
b. it is lighter than air
c. it is one of the constitutents of water
d. it is a noble gas
Q. Ammonial is a mixture of –
a. aluminium powder and ammonium nitrate
b. aluminium powder and ammonium chloride
c. aluminium powder and ammonium sulphate
d. aluminium powder and potassium nitrate
Q. Gelatin is mostly used in making icecreams in order to -
a. prevent making a colloid
b. stabilise the colloid and prevent crystallisation
c. stabilise mixture
d. enrich the aroma
Q. Glycol is added to aviation gasoline because it -
a. reduces evaporation of petrol
b. increases efficiency of petrol
c. prevents freezing of petrol
d. reduces consumption of petrol
Q. Catalyst is a substance which –
a. increases the rate of the reaction
b. decreases the rate of reaction
c. has no action on the rate of the reaction
d. None of these
Q. Table salt gets moist during rainy season because –
a. sodium chloride is hygroscopic
b. sodium chloride is deliquescent
c. sodium chloride contains some quantity of sodium iodide
d. sodium chloride contains hygroscopic impurities like magnesium chloride
Q. Which of the following could be used as fuel in propellant or rockets?
a. Liquid Hydrogen + Liquid Nitrogen
b. Liquid Oxygen + Liquid Argon
c. Liquid Nitrogen + Liquid Oxygen
d. Liquid Hydrogen + Liquid Oxygen
Q. The BOD values of water indicate the
a. amount of organic debris
b. amount of oxygen used for biochemical oxidation
c. amount of oxygen used for biochemical reduction
d. amount of ozone used for biochemical oxidation
Q. The addition of gypsum to port-land cement helps in :
a. increasing the strength of cement
b. rapid setting of cement
c. preventing rapid setting of cement
d. reduction in the cost of cement
Q. What is the name of that system, which uses radioactivity to decide the period of materials of-prehistoric period?
a. Radium dating
b. Uranium dating
c. Carbon dating
d. Deuterium dating
Q. Cement is made hard with –
a. dehydration
b. hydration and dissociation of water
c. Dissociation of water
d. Polymerisation