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प्रश्न
Write true or false :
Hydrogen sulphide has rotten egg smell .
पर्याय
True
False
उत्तर
True
APPEARS IN
संबंधित प्रश्न
State whether the following statement is true or false. In case a statement is false, write the corrected statement.
Condensation of steam is not a chemical change.
When carbon dioxide is passed through lime water, it turns milky due to the formation of ______.
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.
How do the following help in bringing about a chemical change?
light.
Define catalyst.
FILL IN THE BLANK
In a double decomposition precipitation reaction both the reactants must be ............ soluble.
FILL IN THE BLANK
Positively charged ions are called ........
TRUE \ FALSE
Positively charged electrode is called the anode. True or false ?
What are the characteristics of a chemical reaction ? A chemical reaction is characterised by an irreversible change in which a new substance is formed.
Explain the type of reactions on the basis of the direction of reaction.
Explain the following reaction with one suitable example of Decomposition reaction
When electric current is passed through acidulated water ______ of water takes place.
Give an example of the following chemical change.
A reaction where colour change is noticed
What is a chemical change? Give two examples of chemical change?
What is observed in performing the following :
| Hydrogen | Oxygen | Carbon dioxide | Chlorine | |
| Litmus test | ||||
| Apply a burning splint to the gas | ||||
| Colour of gas | colourless | colourless | colourless | greenish-yellow |
| Odour of gas |
State the original colour of the following substance and colour of residue obtained after heating.
Ammonium dichromate
State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
Give a chemical test to distinguish between the following gases.
NH3 and SO2
Distinguish by heating the following in dry test tubs.
Zinc nitrate and copper nitrate.
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.
What is a chemical reaction?
Complete the table given below.
| Heat on copper carbonate | Test for gas evolved |
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 ______.
Which of the following is a chemical change?
Rusting of iron is ______.
We are advised to not to play with fireworks. Give reason.
Write the characteristics of chemical change.
