Advertisements
Advertisements
प्रश्न
Name a non-metal :
- which is lustrous
- which is required for combustion
- whose one of the allotrophic forms is a good conductor of electricity. Name the allotrope.
- other than carbon which shows allotropy
- which is known to form the largest number of compounds
Advertisements
उत्तर
- Iodine is a lustrous non-metal because it is shiny.
- Oxygen is a non-metal that is required for combustion.
- Carbon, Graphite
- Sulphur
- Carbon
APPEARS IN
संबंधित प्रश्न
Match the following
| Column A | Column B | ||
| (a) | Molecules | (i) | Water boils |
| (b) | 100° C | (ii) | Evaporation |
| (c) | 0° C | (iii) | Changes from solid to gas |
| (d) | At all temperatures | (iv) | Matter |
| (e) | Camphor | (v) | Water freezes |
Liquids have definite volume but do not have definite shape.
Give one difference between atoms and molecules.
Which of the following materials fall in the category of a “pure substance”?
- Ice
- Milk
- Iron
- Hydrochloric Acid
- Calcium oxide
- Mercury
- Brick
- Wood
- Air
Name the scientist who studied the movement of pollen grains suspended in water through a microscope. What is this phenomenon known as?
What is Brownian motion? Draw a diagram to show the movement of a particle (like a pollen grain during Brownian motion.
Name two solid, two liquid and two gaseous elements at the room temperature.
Name a metal which can be easily cut with a knife.
A, B and C are all liquids. Liquid A has a comparatively low boiling point. On heating, liquid A vaporises completely without leaving behind any residue. Liquid A is being used increasingly as a fuel in motor vehicles either alone or by mixing with petrol. Liquid B has a very high boiling point. It also vaporises completely on heating, without leaving any residue. Liquid B is a conductor of electricity and used in making thermometers. Liquid C has a moderate boiling point. On heating, liquid C vaporises leaving behind a white solid D which is used in cooking vegetables. The condensation of vapours from C give a liquid E which turns anhydrous CuSO4 to blue.
(a) Which liquid could be an element ? Name this element.
(b) Which liquid could be a mixture ? Name this mixture.
(c) Which liquid could be a compound ? Name this compound.
(d) What could the solid D be ?
(e) What do you think is liquid E ?
State whether colloidal solutions are homogeneous or heterogeneous.
How would you prepare a saturated solution of sodium chloride in water at 25°C ? What will happen if this solution is cooled to 10°C ?
Which of the following is not an emulsion ?
Name the process which can be used to purify an impure sample of copper sulphate.
What is fractional distillation ? What is the use of fractionating column in fractional distillation ?
Matter is made up of ______.
Name the metals that are used in jewellery.
Complete the following table:
| S.No. | CELSIUS | KELVIN |
| 1. | 90°C | 363 K |
| 2. | ______ | 283 K |
| 3. | 63 °C | ______ |
| 4. | 250°C | ______ |
| 5. | ______ | 303 K |
Which statement is not correct for a mixture
The movement of particles in liquids is ______.
