Advertisements
Advertisements
प्रश्न
Select the correct answer for the following options:
The gas obtained when potassium chlorate is heated in the presence of a catalyst.
पर्याय
Hydrogen
Copper [II] oxide
Oxygen
Copper [II] hydroxide
Ammonia
उत्तर
Oxygen
APPEARS IN
संबंधित प्रश्न
Changes in which new substances are formed are called ______ changes.
How would you show that setting of curd is a chemical change?
The gas we use in the kitchen is called liquefied petroleum gas (LPG). In the cylinder, it exists as a liquid. When it comes out from the cylinder it becomes a gas (Change − A), then it burns (Change − B). The following statements pertain to these changes. Choose the correct one.
Complete and balance the following chemical equations:
\[\ce{Pb(NO3)2->[heat]}\] _________
Give reason .
A person suffering from acidity is advised to take an antacid.
FILL IN THE BLANK
The new substances formed during a chemical reaction are called the ..................
TRUE \ FALSE
Electrolytic refining is a method in which a thin coating of a metal is done over another metal.
TRUE \ FALSE
Evaporation of water is a physical change. True or false ?
What are biocatalysts ?
True or false
New substances are formed in a chemical change.
Write true or false :
Hydrogen sulphide has rotten egg smell .
Write true or false.
A chemical equation gives only qualitative information of a chemical reaction.
Balance the following equation :
Fe + H2O → Fe3O4 + H2
Give an example of the following chemical change.
Two gases combine to form white solid
What is a chemical change? Give two examples of chemical change?
Complete and balance the following reaction:
Pb(NO3)2 + KI →
Complete and balance the following reaction:
\[\ce{CuCO3 ->[\Delta]}\]
State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
What do you observe when CO2 is passed through lime water first and then a little in excess.
Give balanced equation for the following conversion affected by heat alone on the substance:
Copper nitrate to nitrogen dioxide
Complete the table given below.
| Heat on ammonium dichromate | Name of neutral gas evolved |
Complete the table given below.
| Addition of dil. H2SO4 to FeS | Odour of gas evolved |
Match the following:
| 1. | Sodium Chloride | a. | CaSO41/2H2O |
| 2. | Calcium sulphate dihydrate | b. | C2H5Oh |
| 3. | Magnesium sulphate hydrate | c. | CaSO4.2H2O |
| 4. | Calcium sulphate hemihydrate | d. | NaCl |
| 5. | Phenol | e. | MgSO4.H2O |
Which of the following is a chemical change?
A chemical change may involve –
Iron benches kept in lawns and gardens get____________. It is a _________ change because a new _________ is formed.
Chemical changes are important in our day-to-day life. Give examples.
What are the chemical reactions that occur in everyday life?
