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प्रश्न
Select the correct answer for the following options:
The pale blue precipitated obtained when copper [II] sulphate reacts with sodium hydroxide.
विकल्प
Hydrogen
Copper [II] oxide
Oxygen
Copper [II] hydroxide
Ammonia
उत्तर
Copper [II] hydroxide
APPEARS IN
संबंधित प्रश्न
Write the missing reactants and products and balance the equations.
................+ HCI `→` NaCI + `"H"_2"O"` + .........................
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Which one of the following alters the rate of the chemical reaction without itself undergoing any change?
- temperature and Pressure
- concentration of reactants
- presence of catalyst
- none of these
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer
Which of the following is a reducing agent?
- oxygen
- chlorine
- hydrogen
- none of these
FILL IN THE BLANK
A .............. change is a temporary change.
TRUE \ FALSE
Copper can displace iron from iron sulphate.
TRUE \ FALSE
Weak electrolytes dissociate partially in their aqueous or fused state.
TRUE \ FALSE
Temperature at which a liquid starts boiling is known as the boiling point of that liquid. True or false ?
What are chemical reactions?
How is precipitate formation in a chemical reaction indicated?
What are the characteristics of a chemical reaction ? A chemical reaction is characterised by an irreversible change in which a new substance is formed.
Write true or false :
No new substance is formed during a chemical 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 |
When electric current is passed through acidulated water ______ of water takes place.
Write the chemical reaction where the following changes are observed.
Physical state is changed
When hydrogen burns in oxygen, water is formed; when electricity is passed through water, hydrogen and oxygen are given out. Name the type of chemical change involved in the two cases.
Multiple choice:
Thermal decomposition of sodium carbonate will produce
What do you observe when H2S is passed through a lead nitrate solution.
Distinguish by heating the following in dry test tubs.
Ammonium Chloride and iodine.
Give a balanced equation for a reaction involving the evolution of gas on the addition of dilute acid to sodium sulphite.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Lead nitrate.
What happens when cane sugar is strongly heated? Mention any two changes in it.
________ is a chemical substance which alters the speed of a chemical reaction.
Which of the following is/are true when milk changes into curd?
- Its state is changed from liquid to semi-solid.
- It changes colour.
- It changes the taste.
- The change cannot be reversed.
Choose the correct option from below:
State whether the following statements are true or false:
When a candle burns, both physical and chemical changes take place.
Iron benches kept in lawns and gardens get____________. It is a _________ change because a new _________ is formed.
Write the chemical reaction of baking soda with lemon.
Assertion (A): Cutting paper into very small pieces is an irreversible change.
Reason (R): Physical changes are always reversible.
Both CO2 and H2 gases are ______.
______ is a chemical substance is used in whitewashing.
