WAEC - Chemistry (2000 - No. 20)
What type of reaction is involved when wood shavings produce a brown gas with concentrated HNO3?
Redox reaction
Destructive distillation
Dehydration
Nutralization
Açıklama
The brown gas produced is nitrogen(iv)oxide (NO2), a common product of nitric acid reactions. Also, note that Nitric acid is a strong oxidizing agent, meaning it readily accepts electrons from other substances. Wood shavings are primarily composed of cellulose, a complex carbohydrate. The reaction between concentrated nitric acid and cellulose involves the oxidation of cellulose by nitric acid, resulting in the formation of nitrogen dioxide(brown gas) and other products. This is an oxidation-reduction reaction (Redox reactions). The correct answer is option A