Because the formation of rust is a kind of chemistry reaction.
After chemistry reaction, compound with new properties is produced.
Of course, color is one of the new properties.
For example, if you put iron in colorless acid solution, a green solution is made.
This kind of chemisty reaction differs from physical reaction, for example, pigment with one color dissolves in liquid, a liquid with same color is made.
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Answer:
H_2O + 2CrO_4^2- + 3SO_3^2- -> 3SO_3^2- + 2CrO_2^- + 2OH^-
Explanation:
Reduction half reaction
2H_2O + CrO_4^2- + 3e -> CrO_2^- + 4OH^-
Oxidation half reaction
2OH^- + SO_3^2- -> SO_4^2- + H_2O + 2e
Balanced overall equation
H_2O + 2CrO_4^2- + 3SO_3^2- -> 3SO_3^2- + 2CrO_2^- + 2OH^-
Answer:
Gravitational force of attraction.
Explanation:
When two bodies of masses 'm' and 'M' are separated by a distance 'r', then both the bodies experience a force of attraction towards each other. This force of attraction is called gravitational force. It is a weak force but it always act between two bodies that have mass.
The magnitude of the gravitational force is directly proportional to product of the masses and inversely proportional to the square of the distance between the masses.
This means that as the distance between the bodies is increases, the gravitational force between the bodies decreases and vice versa.
The gravitational force of attraction is given as:
Answer:
As the amplitude of pendulum motion increases, the period lengthens, because the restoring force −mgsinθ increases more slowly than −mgθ (sinθ≅θ−θ3/3!for small angles).
