An insufficient flow of oxygen while combusting this piece of paper leads to the production of solid carbon particles, which rise through the flame. These particles become hot, burn and ultimately give a yellowish light. That is why a piece of paper will usually burn with a yellow flame.NCERT Solutions of Chapter 6 of Class 8 Science are available at free of cost on the Vedantu website and on the Vedantu app. These solutions have more such experiments and their answers to help you understand complex phenomena easily.