Advertisements
Advertisements
प्रश्न
State what are – ‘stain removals’. Name three important stain removers & give their prime functions.
Advertisements
उत्तर
Stain removals: It is the process of removing a mark or a stain left by one substance on a specific surface fabric. Most stains are removed by dissolving with a solvent.
Examples of stain removers:
| Substance |
Stain |
| Lemon juice | contains citric acid and is used for removing stains from fabrics. |
| Hydrogen peroxide | a mild bleaching agent also effective in removing stains. |
| Glycerine | it softens stains on wool |
संबंधित प्रश्न
What is ‘Philosopher’s stone’?
How is the knowledge of chemistry important to mankind?
Who is known as the Father of chemistry? Why?
Write True or False against the following statement.
Gunpowder is an insecticide:
Match the following scientists in column A with their discoveries or contributions in column B.
| Column A | Column B | ||
| (a) | Marie Curie | (i) | Safety Lamp |
| (b) | John dalton | (ii) | Helium |
| (c) | William Ramsey | (iii) | Nobel Prize Winner (two times) |
| (d) | Sir Humphry Davy | (iv) | Atomic Theory |
State the functions of the following basic glass apparatus:
Glass test tube
Give a comparative difference between soaps and detergents. Give a reason. why detergents have an advantage over soap.
Select the correct name from the choices given below for the following case.
A synthetic fiber used in clothing.
Match the apparatus A to J shown below with their correct names 1 to 10 given below:
1. Delivery Tube
2. Pipette
3. Wire gauze
4. Bee-hive shelf
5. Thistle funnel
6. Flat bottom flask
7. Test tube stand
8. Burette
9. Retort
10. Conical flask
Select the correct apparatus from A, B, or C for the following functions of the apparatus given.
A glass apparatus that measures liquid by sucking the liquid at one end up to the marked level and later pouring it out.
