Advertisements
Advertisements
प्रश्न
Name the process by which common salt is obtained from sea-water.
उत्तर
Common salt is obtained from seawater by the process of evaporation.
APPEARS IN
संबंधित प्रश्न
Fill in the blank
All matter is made up of tiny particles called ______
Out of solids, liquids and gases, which one has :
- maximum movement of particles ?
- maximum interparticle attractions ?
- minimum spaces between particles ?
Draw a flow-chart for the schematic representation of different types of matter.
Which of the following are compounds ?
- CO
- No
- NO
- Co
Iron powder and sulphur powder were mixed together and divided into two parts A and B. When part A was heated strongly over a burner, then a substance C was formed. The part B was, however, not heated at all. When dilute hydrochloric acid was added to substance C, then gas D was evolved and when dilute hydrochloric acid was added to part B then gas E was evolved.
- What type of substance is B ?
- What type of substance is C ?
- Name the gas (i) D, and (ii) E ?
- State one characteristic property of gas D.
- Write one test to identify gas E.
Define solvent.
How will you differentiate between a suspension and a colloid ?
What is a colloid ? Give two examples of colloids (or colloidal solutions)
Which one of the following is not a chemical change ?
When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water.
(a) What type of change occurs when solid A is dissolved in water ? Why ?
(b) What type of change occurs when solid D is dissolved in water ? Why ?
(c) Name a metal which you think could behave like solid A. Also name the products B and C.
(d) Name the solid D if it is the one which is used in making ordinary dry cells.
(e) Name the process by which D can be recovered from E.
What difference in the properties of oil and water enable their separation by a separating funnel ?
Name the process by which common salt is purified.
Describe a method to separate a mixture of common salt and sand.
With the help of a labelled diagram, describe the method of separating ammonium chloride from a mixture of ammonium chloride and common salt. Mention the difference in the properties of ammonium chloride and sodium chloride which has made this separation possible.
The technique which is used to separate particles of a solid suspended in a liquid quickly is called :
There are three liquids A, B and C, all having different densities and different boiling points. Liquids A and C are organic in nature whereas liquid B is considered to be inorganic. When liquids A and B are put together in a container, they form a single layer. On the other hand, when, liquids B and C are mixed, they form two separate layers :
(a) Which process will you use to separate a mixture of A and B ?
(b) Which method will you use to separate a mixture of B and C ?
(c) Name the liquids which would behave like (i) A (ii) B and (iii) C.
Wipe the board with a duster and then tap the duster against the table. What do you see?
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 |
Write a scientific reason.
Lemon sherbat has sweet, sour and salty taste and it can be poured in a glass.
