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प्रश्न
Write true or false.
A chemical equation gives only qualitative information of a chemical reaction.
पर्याय
True
False
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उत्तर
False
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संबंधित प्रश्न
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.
Fill in the blanK
A .............is a substance which changes the rate of a chemical reaction without undergoing a chemical change.
FILL IN THE BLANK
Distillation is a method of obtaining pure ............. from a solution.
Differentiate between in Chemical reaction and chemical equation.
Explain,giving one example of the following chemical changes:
Reversible reaction
Give a chemical test to distinguish between the following gases.
SO2 and Cl2
Distinguish by heating the following in dry test tubs.
Zinc carbonate, Copper carbonate and lead carbonate.
Write your observation and a balanced equation in the case of the following substances being heated.
Zinc carbonate.
Represent the addition of dilute sulphuric acid to zinc by means of a chemical equation. State the function of the arrow between the reactants and products.
A chemical reaction is often accompanied by external indications or characteristics which include –
- Colour change
- Effervescence or gas evolved
- Evolution or absorption of heat
- Formation of a precipitate.
With reference to each of the above indications, state the external indication seen during – Thermal decomposition of mercury [II] oxide.
State the following reaction represent oxidation or reduction.
\[\ce{Al->Al+++}\]
State whether the following reaction is oxidation or reduction.
\[\ce{Na->Na+}\]
Give a balanced equation for the conversion of a soluble lead salt to an insoluble lead salt – formed as a white precipitate.
Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
Arrange the following statements in correct sequence:
- One side is water-loving and other water-hating molecules.
- When you agitate the cloth, the dirt is surrounded by many molecules and taken away from the cloth.
- The dirt surrounded by the detergent molecules floats in the water making it dirty.
- Finally, the cloth is clean.
- The detergent molecules have two sides.
- Water hating goes and joins with dirt and oil in the cloth while the water-loving joins with the water molecules.
Rusting of iron is ______.
Give an example where heat, light, and sound are produced during a chemical change.
Why is spoiling food a chemical change?
The reaction of H2 gas with oxygen gas to form water is an example of ______.
