Tag: rocks and minerals

CNG is made by compressing natural gas (which is mainly composed of methane, CH₄ stored at high pressure), to less than 1 percent of the volume, it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of 20–25 MPa (2,900–3,600 psi), usually in cylindrical or spherical shapes.

Methane is the important constituent (95%) of natural gas. Methane has high heat of combustion. Hence, it is used as fuel.
$CH _4 + 2O _2 \rightarrow CO _2 + 2H _2O + heat$

Fractional distillation is used for refining of petroleum.

The number of carbon atoms in petrol is $C _{7}-C _{9}$.

Natural gas is primarily composed of methane, but also contains ethane, propane and heavier hydrocarbons. It also contains small amounts of nitrogen, carbon dioxide, hydrogen sulphide and trace amounts of water.

LPG is liquefied petroleum gas. The main components are:

In its strictest sense, petroleum includes only crude oil, but in common usage, it includes all liquid, gaseous and solid hydrocarbons.Under surface pressure and temperature conditions, lighter hydrocarbons methane, ethane, propane and butane occur as gases, while pentane and heavier hydrocarbons are in the form of liquids or solids.

Because heavier crude oils have too much carbon and not enough hydrogen, the cracking processes generally involve removing carbon from or adding hydrogen to the molecules and using fluid catalytic cracking to convert the longer, more complex molecules in the oil to the shorter, simpler ones in the fuels.

In the reservoir, crude oil is usually found in association with natural gas, which is lighter forms a "gas cap" over the petroleum, and saline water which, being heavier than most forms of crude oil, generally sinks beneath it.

Petroleum is a mixture of a very large number of different hydrocarbons; the most commonly found molecules are alkanes(kinds of paraffin), cycloalkanes(naphthenes), aromatic hydrocarbons, or more complicated chemicals like asphaltenes. Each petroleum variety has a unique mix of molecules, which define its physical and chemical properties, like colour and viscosity.