Answer:
One nucleophilic center
Explanation;
Nucleophile:
Nucleophile is a substance which is nucleus loving in nature (<em>Nucleo</em>; Nucleus , <em>phile</em>; Loving). It is known as a specie which donates a lone pair of electrons to electrophile (electron loving) in a chemical reaction.
Thus, Nucleophile is the region of higher electron density in a molecule and attacks on the lower electron density region of another molecule. Also, the nucleophile can also contain a negative charge.
Number of Nucleophilic centers in Methanol:
The chemical structure of Methanol is attached below and it can be observed that the oxygen atom is containing two lone pair of electrons. Hence, the oxygen atom can act as a nucleophilic center. Therefore, there is only one nucleophilic center in methanol.
H₃C-OH + H₃C-Br → H₃C-O-CH₃ + HBr
In above reaction methanol is acting as a nucleophile and is attacking on electrophilic center (Carbon) of methyl bromide yielding dimethyl ether.
Water is called a universal solvent because of its ability to dissolve different types of substances.
The basic unit of life is cell and a large portion of living cell (60%) is made up of water, this is because cells need water to survive. Biochemical reactions are always ongoing in the living cells and water act as solvents under which these reactions occur. Because of the high solubility of water, it is able to dissolve various substances needed by the body, this makes it easy for the substance to participate in chemical reactions and to move from one point to another. Without water biochemical reactions will not be able to occur in cells and this will lead to the death of the cells.
Plate is in the process of splitting into two tectonic plates
A) The techtonic plates are moving apart