Why are carbon and its compounds used as fuels for most applications?
Most of the carbon compounds give a lot of heat and light when burnt in air. Saturated hydrocarbons burn with a clean flame and no smoke is produced. The carbon compounds, used as a fuel, have high calorific values. Therefore, carbon and its compounds are used as fuels for most applications.
Write notes on the following:
(a) Saturated and unsaturated hydrocarbons
(b) Corrosion
(c) Precipitation reaction
Match Column-I with Column-II and choose the correct option:
| Column-I (Minerals) | Column-II (Features) | ||
|---|---|---|---|
| A. | Copper | (i) | Used in manufacturing of steel and plants |
| B. | Bauxite | (ii) | Used in electric and electronic industries |
| C. | Mica | (iii) | Used in electric cables and utensils |
| D. | Manganese | (iv) | Used in aluminium production |
Choose the correct answer from the options given below:
Give reasons:
(i) The sky appears dark to passengers flying at very high altitudes.
At very high altitudes, passengers are above the atmosphere where there is less scattering of sunlight. As a result, they do not see the scattered blue light and the sky appears dark, similar to the condition experienced by astronauts in space.
(ii) 'Danger' signal lights are red in color.
The existence of a chemical element in one or more physical forms happening in the same physical state is called Allotropes or allotropy. Allotropes may show different physical or chemical states turning on the atom arrangement or the number of existent atoms. While carbon and sulfur is the common element presenting allotropy. Carbon can make further allotropes due to its five-membered valency.
Read More: Allotropes of Carbon
Carbon is part of a p-block element.
The crystalline form of carbon consists of allotropes like;