Question

in this reaction, is the water acting as an acid, a base, an oxidant or a reductant? please explain it

Answer 1

\[Mg+2H _{2}O \rightarrow Mg(OH)_{2}+H _{2}\]

Answer 2

base

Answer 3

why is it?

Answer 4

The water is not a base because it is not accepting a proton (H+)

Answer 5

Mg + 2H2O --> mg(OH)2 + H2 In this reaction Mg --> Mg2+ ( Oxidation)

H2O --> H2 ( reduction )

Hence , In the above reaction water act as a reduction ( gain of electron)

Answer 6

No, water is reduced (to hydrogen), so it is an oxidizing agent.

Answer 7

First, you can see that the Mg is being oxidized, as it is going from an oxidation state of 0 in the metal to +2 as the Mg+2 cation in the ionic compound Mg(OH)2. That implies that the water is behaving as an oxidant (oxidizing agent), and is itself being reduced. You can confirm this by noting that one of the Hs in the H2O goes from an oxidation state of +1 in the H2O to an oxidation state of 0 in the H2 gas.

If we choose to regard the Mg(OH)2 as a coordinate complex, which is kind of a stretch, because there will probably be very little electron sharing between the Mg+2 cation and the oxygens, then when the Mg(OH)2 forms (which may not be until the solution is dried, if this occurs in aqueous solution), then we can identify the association of the Mg+2 and the OH- as a Lewis acid-base reaction, in which the oxygen atoms on the OH- donate a pair of electrons to form a coordinate covalent bond to the Mg+2, which is acting as a Lewis acid. But this is not likely to be what you're being asked. I would say the most plainly correct answer is that water is acting as an oxidant.