carbon and its compounds — Science STD 10 — Question
Gujarat BoardEnglish MediumSTD 10Sciencecarbon and its compounds2 Marks
Question
Give scientific reasons : Candle burns with a yellow flame.
✓
Answer
Candle is made-up of wax, which consists of saturated hydrocarbons containing $18$ to $20$ carbon atoms.
When a candle is lighted (ignited), the wax melts which rises up the wick and gets covered by vapour. As a result, there is no proper mixing of $O_2$ of air and wax vapours.
Therefore, here incomplete combustion of wax takes place, and complete combustion of wax does not take place.
Furthermore, incomplete combustion of wax produces unburnt carbon particles, which rise up in the flame, get heated and imparts yellow colour to the flame.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.