Advertisements
Advertisements
प्रश्न
A chemical reaction is a temporary reaction.
विकल्प
True
False
Advertisements
उत्तर
A chemical reaction is a temporary reaction- False.
Correct statement:
A chemical reaction is permanent.
APPEARS IN
संबंधित प्रश्न
CFC is a pollutant.
Match the following.
| Spoilage | Decomposition |
| Ozone | Biocatalyst |
| Tarnishing | Oxygen |
| Yeast | Chemical reaction |
| Calcium oxide | Food |
What is tarnishing? Give an example.
Burning of fossil fuels is responsible for global warming. Justify the statement.
Do all the fruits and vegetables undergo browning? Explain.
Classify the following day-to-day activities based on chemical reactions by physical contact, solutions of reactants, heat, light, electricity, and catalyst.
- Burning of crackers during festivals
- Fading of coloured clothes on drying under sunlight.
- Cooking of eggs.
- Charging of batteries.
Kumar is going to build a house. To purchase the iron rods required for construction, he visited an iron and steel shop nearby. The seller showed him some iron rods which are fresh and good. He also showed him little older iron rods which are brownish in appearance. The price of fresh rods is more than the older ones. The seller also gave some offers to older ones. Kumar’s friend Ramesh advised him not to buy the cheaper rods.
- Is Ramesh right in his suggestion?
- Could you explain the reason for his suggestion?
- What are the values shown by Ramesh?
When a magnesium ribbon is burnt in the air, the ash formed is ______.
Reason out
Ozone is produced naturally in the stratosphere.
An element ‘A’ on exposure to moist air turns reddish-brown and a new compound ‘B’ is formed. The substance ‘A’ and ‘B’ are:
