Answer:
NH3(aq)
Explanation:
Gold III hydroxide is an inorganic compound also known as auric acid. It can be dehydrated at about 140°C to yield gold III oxide. Gold III hydroxide is found to form precipitates in alkaline solutions hence it is not soluble in calcium hydroxide.
However, gold III hydroxide forms an inorganic complex with ammonia which makes the insoluble gold III hydroxide to dissolve in ammonia solution. The equation of this complex formation is shown below;
Au(OH)3(s) + 4 NH3(aq) -------> [Au(NH3)4]^3+(aq) + 3OH^-(aq)
Hence the formation of a tetra amine complex of gold III will lead to the dissolution of gold III hydroxide solid in aqueous ammonia.
The balanced reaction is:
MnO2<span>(s) + 4HCl(aq) → Cl2(g) + MnCl2(aq) + 2H2O(l)
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We are given the amount of hydrochloric acid to be used for the reaction. This will be the starting point for the calculations.
1.82 mol HCl ( 1 mol Cl2 / 4 mol HCl) = 0.46 mol Cl2
Therefore, 0.46 mol of chlorine gas is produced for the reaction of hydrochloric acid and manganese oxide.
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.
