Consider this reaction: Mg(s) + 2H20(1) ► Mg(OH)2(s) + H2(9)

What is the oxidation state of Mg in Mg(s)?

Oxidation state for Mg(s) is 0

Explanation:

This is redox reaction, where one element is oxidized and another is reduced.

H from water is being reduced while the Mg which is in ground state is oxidized.

When the element is reduced, the oxidation state is decreased:

2H⁺ + 2e⁻  ⇄  H₂

When the element is oxidized, the oxidation state is increased

Mg ⇄ Mg²⁺ + 2e⁻

As Mg(s) in the product side, is at ground state, the oxidation state is 0.

Any element in ground state has 0, as oxidation state.

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.