drive the de Broglie equation for du nature of the matter in hindi
Answers
Answer:
1. (a) Define Rusting
Ans. The process of slow eating of the surface of metal iron when exposed to air for a longer period of time is called rusting.
(b) Why do you apply paint an iron articles?
Ans. We apply paint on iron articles because it forms a protective coating on the surface of
iron and we can protect it against rusting.
2. What are neutralization reactions? Why are they named so? Give one example?
Ans. A neutralization reaction is the chemical reaction between an acid and base dissolvedi n water
For Ex- KOH + HNO3 -------> KNO3 + H20
It is called neutralization reaction because both and formed as the products, are neutralin nature.
3. What is balanced chemical equation? Why should chemical equation be balanced?
Ans. The reaction in which the number of atoms of each element is equal on the reactant
side and product side is called balanced equation. Chemical reaction should be balanced
because only a balanced equation tells us the relative quantities of different reactants and
products involved in the reaction.
4. How is plaster of Paris chemically different from gypsum? How may these be inter
converted? Write one use of plaster of Paris?
Ans. Plaster of Paris is different from Gypsum as it is prepared from heating gypsum. Plaster
of Pairs is a major constituent of surgical bandages used for setting fractured bones. Before
applying on fractured bone, it is made wet with water and as a result of hydration it changes
into gypsum which keeps the bones in position.
These may be interconverted by the reaction.
CaSo4•1/2H20 + 3/2H20 -------> CaSo4•2H2O
(Plaster of Paris) (Gypsum)
The use of plaster of Paris are-
(i) It is used for making modules or casts for toys pottery, ceramics etc.
(ii) In surgical bandages for setting fractured bones.
5. Give two important uses of washing soda and baking soda.
Ans. Uses of washing soda are :-
(i) As cleansing agent.
(ii) Removing permanent hardness of water.
(iii) Used in glass, soap and paper industries.
Uses of baking soda are :-
(i) For making baking powder.
(ii) As ingredient of antacid.
6. (a) What is corrosion?
Ans. The eating up of the surface of metal if kept open for a long time is called corrosion.
(b) How is corrosion caused?
Ans. It is caused due to the eating of metals by the gasses and water vapours present in air due to the formation of certain chemical compound.
7. Define the following terms :
a) Minerals
Ans. The element or compounds which occur naturally in the earth crest are known as minerals.
b) Ores
Ans. Minerals from which metal can be extracted profitably and easily are called ores.
c) Gangue
Ans. Impurities such as soil and sand which are present in the minerals are called gangue.
8. What is a homologous series? Explain with an example. State any two characteristics of homologous series?
Ans. A series of similarly constituted compounds in which the members present have the
same functional group, same chemical properties and any two successive members is a