Question

while doing an experiment to see burning characteristics of various fibre Prakash hold the cotton
fibre in his hand and was about to burn it on the burner. On seeing this, his classmate Ratan stopped
himmediately and asked to use tong to hold the fibres.
a) What is fibre?
Name any three natural fibres
What are the burning characteristics of the above three fibres?
what value of Prakash is shown here?​

Answer 1

hope it helps little bit

• Fibre is a complex carbohydrate (type of sugar) but unlike other carbohydrates, which are broken down by the body to provide fuel in the form of glucose, fibre cannot be digested by the human body.
• Plant fibres include seed hairs, such as cotton; stem (or bast) fibres, such as flax and hemp;leaf fibres, such as sisal; and husk fibres, such as coconut. Animal fibres include wool, hair and secretions, such as silk.
• The fabric which burns giving a smell of burning hair will be natural silk or pure silk. 2. The fabric which burns giving a smell of burning paper will be artificial silk. Just like silk, wool is also made up of proteins.

Answer 2

Answer:  a.] The thin strands of thread that is made up of still made up of thinner strands are called fiber.

b.]Cotton, Wool, Silk.

c.] 1. Cotton: Ignites on contact with flames; burns quickly and leaves a yellowish to orange afterglow when put out. Does not melt. It has the odor of burning paper, leaves, or wood. The residue is a fine, feathery, gray ash.

2. Wool: Burns with an orange sputtery color, but does not melt. It shrinks from the flame. It has a strong odor of burning hair or feathers. The residue is a black, hollow irregular bead that can be easily crushed into a gritty black powder.

3. Silk: Burns slowly, but does not melt. It shrinks from the flame. It has the odor of charred meat (some say like burned hair). The residue is a black, hollow irregular bead that can be easy to a gritty, grayish-black ash powder.

d.] The value Ratan shows is his caring, and helpfulness towards his friend Prakash.