Silicon is used in –
Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same ?
(i) Good thermal conductivity
(ii) Good electrical conductivity
(iv) High melting point
When iron is left exposed in open air, it gets rusted. Which constituent(s) of air is /are responsible for rusting iron?
(i) Oxygen gas present in air
(ii) Moisture present in air
(iii) Carbon dioxide gas present in air
Select the correct answer using the code given below :
Both oxygen and moisture present in air cause rusting of iron.
Consider the following statements:
Nitrogen is an essential constituent of
Which of the statements given above is/are correct ?
Nitrogen is a essential constituent of all vegetables and animal proteins. Soil contains nitrogen as ammonium salts.
Consider the following elements:
Which of the above elements exist free in nature?
Cu, Au, Ag are known as coinage metals and occur free in nature. Because of nobility they are frequently found in their natives state.
Which of the following statements regarding non-metals is false?
The black material inside a pencil is not metal lead. Actually it is graphite, a non-metal.
Which of the following statement regarding non-metals is true?
Which of the following statement is false?
Gold and Silver are most malleable metals where as zinc metal is non-malleable and brittle.
Which of the following statement regarding metals is true?
Mercury being a metalis liquid at room temperature. Metals are good conductor of heat therefore cannot be used to make handle it will result into burns. Gold cannot be used to make electrical wires it is very expensive therefore metals like copper is used for it
Which of the following non-metals sublimes on heating ?
Iodine is a sublime substance