Answer:
Chemistry is the branch of science that deals with the properties, composition, and structure of elements and compounds, how they can change, and the energy that is released or absorbed when they change. Traditionally, chemistry has been broken into five main subdisciplines: Organic, Analytical, Physical, Inorganic and Biochemistry. Chemistry is involved in everything we do. The reason why chemistry touches everything we do is because almost everything in existence can be broken down into chemical building blocks.
Explanation:
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The 2 in front of
in
is <u>Coefficient.</u>
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The
after
in the same equation is <u>sub </u><u>script</u><u>.</u>
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There are two atoms of
in 
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Answer: None of the given options show polymer made up of H₂C=CH-CN (Acrylonitrile).
Explanation: Acrylonitrile (H₂C=CH-CN) which is a monomer on self linkage results in a large chain polymer called as
Polyacrylonitrile.
The structure of Polyacrylonitrile is as follow,
--(H₂C-CHCN-)n--Where n shows the number of Acrylonitrile units joined together in the formation of Polyacrylonitrile. This polymerization reaction can take place by different mechanisms including free radical mechanism, acid catalyzed addition or base catalyzed addition reaction.
The polymerization is shown below,
Copper oxide(solid) + Sulphuric Acid (aqueous)-> Copper Sulphate (aqueous)+ Water(liquid)
In equation form:
CuO +H2SO4 -> CuSO4 + H2O
The colour change you will see is black to blue as Copper oxide is usually found as a black powder. Upon the reaction with sulphuric acid it will change to a cyan blue.
If you heat the made solution of copper sulphate, the water will evaporate and you will be left with white anhydrous copper sulphate crystals.