During combustion of unsaturated compounds a ______ is seen. (1) clean flame (2) blue flame (3) red flame (4) yellow flame

During combustion of unsaturated compounds a ______ is seen. (1) clean flame (2) blue flame (3) red flame (4) yellow flame
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(4) yellow flame Explanation: When saturated compounds are burnt in air,they give a clear(blue) flame due to complete combustion. However the burning of unsaturated compounds (alkenes and alkynes) gives a sooty (yellowish) flame due to incomplete combustion.
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