State reasons for the following :
(a) Iron articles get coated with a reddish brown powder when left for sometime in open. (b) Burning of coal is an exothermic reaction.(c) The chemical equations should be balanced.

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Solution

Dear Student

a) iron articles react get coated with reddish brown powder , i e rust ( coatings of oxides etc) on reacting with moisture and air , when kept in open.
b) burning of coal is exothermic because it is a combination reaction and large amount of heat is released.
c) to satisfy the law of conservation of mass.

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State reasons for the following : (a) Iron articles get coated with a reddish brown powder when left for sometime in open. (b) Burning of coal is an exothermic reaction.(c) The chemical equations should be balanced.

State reasons for the following :
(a) Iron articles get coated with a reddish brown powder when left for sometime in open. (b) Burning of coal is an exothermic reaction.(c) The chemical equations should be balanced.