Advertisements
Advertisements
Question
Give two examples where a chemical reaction is accompanied by a change in colour of the reactants and products on completion of the reaction.
Advertisements
Solution
(i) \[\ce{\underset{\text{magnesium}}{Mg} + \underset{\text{Blue copper sulphate}}{CuSO4} ->\underset{\text{colourless magnesium sulphate}}{MgSO4}+\underset{\text{copper}}{Cu}}\]
(ii) \[\ce{2Pb[NO3]2->\underset{\text{litharge (yellow)}}{2PbO} + 4NO2 + O2}\]
(iii) \[\ce{\underset{\text{colourless}}{Pb[NO3]} + 2Kl->\underset{\text{yellow ppt.}}{Pbl2 v} + 2KNO3}\]
APPEARS IN
RELATED QUESTIONS
Define catalyst.
Complete and balance the following chemical equations:
Zn + `"H"_2"SO"_4` `→`
(dil)
TRUE \ FALSE
Evaporation of water is a physical change. True or false ?
Explain the following reaction with one suitable example of Combination reactions .
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 |
Give an example of a reaction where the following are involved:
Close contact
What do you observe when Cl2 is passed through potassium iodide (KI) solution.
Complete the table given below.
| Addition of dil. H2SO4 to KHCO3 | Name of residue obtained |
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Lead nitrate.
Beating an egg to make a cake is a ______.
