(a) The equation for this reaction is (1)A C 2 H 6 + Cl 2 oC 2 H 5 Cl + HCl B C 2 H 6 + Cl 2 oC 2 H 4 Cl 2 + H 2 C C 2 H 6 + Cl 2 o2CH 3 Cl D C 2 H 4 + Cl 2 oC 2 H 4 Cl 2 (b) The role of the UV radiation in the reaction is to (1)A break the Cl Cl bond forming Clâ¢ free radicals.i) Write a chemical equation to show how the presence of carbon dioxide in water results in the formation of carbonic acid. State symbols are not required. (1) (ii) Write the ionic equation to show how acids react with carbonates.State symbols are not required.
A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up
Short-period Comets A comet with an orbital period of less than 200 years is known as a short-period comet or a âperiodic cometâ. These are now divided into Jupiter-family comets with periods less than 20 years and orbits that do not extend much beyond Jupiter, and Halley-type comets with periods of 20â200 years and highly inclined orbits.