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प्रश्न
Name Affects the acidified K2Cr2O7 paper and also turns lime water dirty milky.
उत्तर
SO2
APPEARS IN
संबंधित प्रश्न
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.
What are (i) positive catalysts and (ii) negative catalysts? Support your answer with one example for each of them.
Fill in the blank:
The substances which undergo chemical change are called _______
State what you would observe when the following substance is heated in a glass test tube red lead.
State what you would observe when the following substance is heated in a glass test tube Copper (II) carbonate Red lead .
Explain the following reaction with one suitable example of Decomposition reaction
Explain the following reaction with one suitable example of Double decomposition reaction.
Match the pairs.
| a. | Photosynthesis | i. | Tendency to lose electrons |
| b. | Water | ii. | Reactant in combustion process |
| c. | Sodium chloride | iii. | Chemical change |
| d. | Dissolution of salt in water | iv. | Covalent bond |
| e. | Carbon | v. | Ionic bond |
| f. | Fluorine | vi. | Physical change |
| g. | Magnesium | vii. | Tendency to form anion |
Define:
Photochemical reaction
Give one example
What do you observe when CO2 is passed through lime water first and then a little in excess.
Distinguish by dilute sulphuric acid.
Sodium Sulphite and sodium carbonate?
Distinguish by dilute sulphuric acid.
Copper and magnesium?
Select the correct answer for the following options:
The gas obtained when potassium chlorate is heated in the presence of a catalyst.
Give reason for the following:
A characteristic change of colour is seen when a piece of iron is added to copper [II] sulphate solution.
State the following reaction represent oxidation or reduction.
\[\ce{Al->Al+++}\]
State whether the following reaction is oxidation or reduction.
\[\ce{Na->Na+}\]
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Ammonium dichromate.
Which of the following is not an “element + element → compound” type reaction?
Silver articles turning black: ______:: Boiling of H2O: physical change ______.
