Which one among the following is not a chemical change?
Curdling of milk
Ripening of fruit
Evaporation of water
Burning of coal
Examine these two statements carefully and select the answer.
Statement I : Very little hydrogen is produced when sulphuric acid is added to calcium.
Statement II: The salt that is produced, calcium sulphate, is insoluble.
Both the statements are individually true and Statement II is the correct explanation of Statement I
Both the Statements are individually true but Statement II is not the correct explanation of Statement I.
Statement I is true but Statement II is false.
Statement I is false but Statement II is true.
Examine these two statements carefully and select the answer.
Statement I : Zinc is used for galvanization to protect iron from rusting.
Statement II : Zinc is more reactive towards oxygen than iron.
Both the statements are individually true and Statement II is the correct explanation of Statement I
Both the Statements are individually true but Statement II is not the correct explanation of Statement I.
Statement I is true but Statement II is false.
Statement I is false but Statement II is true.
Calcium ammonium nitrate (CAN) is a popular nitrogen fertilizer because it is
slow supplier of nitrogen
having more percentage of nitrogen in it
fixing the nitrogen in the soil
capable of making the soil acidic
A.
slow supplier of nitrogen
Chromium oxide is used as an ingredient in paints to obtain
green colour
blue colour
red colour
violet colour
A mixture of sodium chlorides and naphthalene can be separated by
extraction with hot water
extraction with cold water
sublimation
steam distillation
The pH of the solution obtained by dissolving pure sodium chloride in water is
acidic
basic
neutral
dependent on the amount of sodium chloride dissolved in water
Oxygen on reaction with non-metals forms oxides, which are
basic oxides
acidic oxides
amphoteric oxides
neutral oxides