Tag: carbon cycle

The ranks are as follows:

(i) Anthracite (ii) Bituminous coal (iii) Sub-bituminous coal (iv) Lignite

Peat is mainly composed of wetland vegetation. Therefore, principally bog plants including mosses, sedges and shrubs. So, it is organic sediment.

Based on this four types of coal are generated:-

(i) Anthracite= $90$% carbon

(ii) Bituminous= $70$% carbon

(iii) Lignite= $40$% carbon

(iv) Peat= $28$% carbon

Anthracite has highest % of carbon.

Due to highest carbon content and fewest impurities, anthracite is the highest grade of coal, whose surface is shining and has the highest calorific value.

 $10^8$

Thermal neutron, any free neutron (one that is not bound within an atomic nucleus) that has an average energy of motion (kinetic energy) corresponding to the average energy of the particles of the ambient materials. Relatively slow and of low energy, thermal neutrons exhibit properties, such as large cross sections in fission, that make them desirable in certain chain-reaction applications. Furthermore, the long de Broglie wavelengths of thermal neutrons make them valuable for certain applications of neutron optics. Thermal neutrons are produced by slowing down more energetic neutrons in a substance called a moderator after they have been ejected from atomic nuclei during nuclear reactions such as fission.

Geothermal energy is the heat from the Earth. It is clean and sustainable. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma.

$4.0 MeV$

Energy released in most nuclear reactions is much larger than in chemical reactions, because the binding energy that holds a nucleus together is far greater than the energy that holds electrons to a nucleus. For example, the ionization energy gained by adding an electron to a hydrogen nucleus is $13.6 eV$—less than one-millionth of the $17.6 MeV$ released in the deuterium–tritium (D–T) reaction.  The complete conversion of one gram of matter would release $9\times10^{13}$ joules of energy. Fusion reactions have an energy density many times greater than nuclear fission; the reactions produce far greater energy per unit of mass even though individual fission reactions are generally much more energetic than individual fusion ones, which are themselves millions of times more energetic than chemical reactions. Only direct conversion of mass into energy, such as that caused by the annihilatory collision of matter and antimatter, is more energetic per unit of mass than nuclear fusion.

Anthracite is coal of a hard variety and contains relatively pure carbon and burns with little flame and smoke. The carbon content is highest. Very few impurities are present. The energy density is highest in Anthracite when compared to all types of coal except for graphite. Anthracite has the highest ranking of coal.

Greenhouse effect, a warming of Earth’s surface and troposphere (the lowest layer of the atmosphere) is caused by the presence of water vapour, carbon dioxide, methane, and certain other gases in the air. Of those gases, known as greenhouse gases, water vapour has the largest effect. The atmosphere allows most of the visible light from the Sun to pass through and reach Earth’s surface. As Earth’s surface is heated by sunlight, it radiates part of this energy back toward space as infrared radiation. This radiation, unlike visible light, tends to be absorbed by the greenhouse gases in the atmosphere, raising its temperature. The heated atmosphere in turn radiates infrared radiation back toward Earth’s surface. 

So the correct option is 'accumulation of CO$ _2$ and depletion of O$ _3$'.