Olympiad Test: Coal And Petroleum

When coal burns in air, the carbon component of the coal comes in contact with the oxygen in the air and releases carbon dioxide CO₂  when combined.

The correct option is C.
The coal tars are generally variable and complex mixtures of poly cyclic aromatic hydrocarbons, phenol as well as hetero cyclic compounds. Totally, there are roughly about 200 substances present in coal tar

The U.S. petroleum industry began in 1859 when a former railroad conductor drilled a well 69.5 feet deep in Northwestern Pennsylvania.

The correct option is Option C.
Coal is called a fossil fuel because it was made from plants that were once alive! Since coal comes from plants, and plants get their energy from the sun, the energy in coal also came from the sun. The coal we use today took millions of years to form. Heat and pressure turned the dead plants into coal.

Fuels burn when they react with oxygen in the air. If there is plenty of air, complete combustion happens.  Coal is mostly carbon. During complete combustion, carbon is oxidized to carbon dioxide:
carbon + oxygen -- carbon dioxide
If there is insufficient air for complete combustion, incomplete combustion (also called partial combustion)  happens. Hydrogen is still oxidized to water, but carbon monoxide forms instead of carbon dioxide.

So, the correct answer is 'Carbon monoxide'.

When wood is heated above 270° C it begins to carbonize. If air is absent, the final product is charcoal. When the wood is dry it's temperature rises, and at about 270°C , it begins to spontaneously decompose. 

On 26 March 1867, oil was struck at  merely 118 feet(35.97-m) in Asia's first mechanically drilled well at Makum  near Margherita area of upper Assam.

 Plants contain mainly carbon, which gets converted into coal. Hence, the slow process of conversion of dead vegetation into coal is called carbonisation.

Petroleum is also known as Black Gold -  because when crude oil is extracted from the land it is black in color. People call it gold because of its oils and value . It is very difficult to find. So it is called Black Gold.