Advertisements
Advertisements
प्रश्न
Give reason why graphite is used for making elecrode in a dry cell.
Advertisements
उत्तर
Graphite is a non-corrosive non-metal and a good conductor of electricity. It is also cheap and insoluble in water, acids and bases. It is inert (does not react) to the electrolytes present in the dry cells. Thus, it makes a good material for an electrode.
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 |
The inter-molecular space is maximum in
Select the correct alternative
The molecules can move freely anywhere in
- gases
- liquids
- solids
- none of the above
Name the processes involved in two cases.
What is meant by saying that metals are lustrous ?
State two physical properties on the basis of which metals can be distinguished from non-metals.
What are the three general classes of matter ? Give one example of each type.
In the following set of substances, one item does not belong to the set. Select this item and explain why it does not belong to the set :
Hydrogen, Oxygen, Steam, Chlorine
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.
What is the most common way of expressing the concentration of a solution ?
What is the difference between solutions and colloids ?
What is a suspension ? Give two examples of suspensions.
How will you separate a mixture of common salt, sulphur powder and sand ?
Explain how, nitrogen , oxygen and argon gases are separated from air.
Naphthalene can be separated from sand :
What type of matter glass is?
Which of the following are homogeneous in nature?
(i) ice
(ii) wood
(iii) soil
(iv) air
Define the term matter.
Define the term matter.
Write a scientific reason.
Lemon sherbat has sweet, sour and salty taste and it can be poured in a glass.
