Tin reacts with nitric acid according to the following equation. what substance is the reducing agent? sn(s) + 4hno3(aq) → sno2(s) + 4no2(g) + 2h2o(g)

Reducing agent in the given reaction is Sn.

Explanation: Reducing agents are defined as the reagents which reduces the other substance and itself gets oxidized.

Oxidation reactions are defined as the reactions in which loss of electrons occur. the oxidation state of the substance is increased in this type of reaction.

For a given chemical reaction:

On reactant side:

Oxidation state of Hydrogen = +1

Oxidation state of oxygen = -2

Oxidation state of Nitrogen = +5

Oxidation state of Sn = 0

On product side:

Oxidation state of Hydrogen = +1

Oxidation state of oxygen = -2

Oxidation state of Nitrogen = +4

Oxidation state of Sn = +4

From above, the oxidation state of Sn is increasing. So, this element will undergo oxidation reaction and hence, is considered as a reducing agent.

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

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