Advertisements
Advertisements
प्रश्न
Write true or false :
When iron and sulphur are heated together a grey mass is formed which is attracted by a magnet .
विकल्प
True
False
Advertisements
उत्तर
False
APPEARS IN
संबंधित प्रश्न
How do the following help in bringing about a chemical change?
heat.
FILL IN THE BLANK
Negatively charged ions are called ..........
FILL IN THE BLANK
The new substances formed during a chemical reaction are called the ..................
TRUE \ FALSE
Copper can displace iron from iron sulphate.
Write true or false :
Hydrogen sulphide has rotten egg smell .
Explain the following reaction with one suitable example of Combination reactions .
Explain the following reaction with one suitable example of Decomposition reaction
Explain the following reaction with one suitable example of Displacement reaction.
Show with the help of diagram of electronic configuration how the following compound is formed from the constituent atoms.
Hydrogen chloride
Define an electrochemical reaction.
When hydrogen burns in oxygen, water is formed; when electricity is passed through water, hydrogen and oxygen are given out. Name the type of chemical change involved in the two cases.
Give examples of exothermic reactions i.e. heat evolved in each of the following:
(a) reaction between a solid and a liquid
(b) reaction between two gases
Give two examples of exothermic reactions seen in everyday life.
Select the correct answer for the following options:
The gas which reacts with oxygen to give a neutral liquid.
Give a word equation for the following reaction.
An exothermic reaction where both the reactants are gases, one of which is oxygen.
Give balanced equation for the following conversion affected by heat alone on the substance:
Zinc nitrate to nitrogen dioxide
______ gas causes tears in our eyes while cutting onions.
A reaction between an acid and a base is called ______.
When an aqueous solution of potassium chloride is added to an aqueous solution of silver nitrate, a white precipitate is formed. Give the chemical equation of this reaction.
The changes in which new substance with new chemical properties are formed are ______.
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.
Can you change rust back into iron by some simple method?
