Advertisements
Advertisements
प्रश्न
Explain, giving one example of the following chemical change:
Thermal dissociation
Advertisements
उत्तर
A reversible decomposition reaction brought about only by heat is called thermal dissociation reaction.
Heat some solid ammonium chloride in a test tube. Two colourless gases, ammonia and hydrogen chloride, are produced. As these gases move up to the upper part of the cooler test tube, they combine to form ammonium chloride, which appears as a white sublimate on the upper cooler side of the test tube.
\[\ce{NH4Cl <=> NH3 \uparrow + HCl \uparrow}\]
APPEARS IN
संबंधित प्रश्न
On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.
A coloured substance which decomposes violently leaving a coloured residue and evolving two neutral gases one of which is unreactive or inert in nature.
Select the correct salt from list II which on thermal decomposition exhibits the change in colour from list I.
| List I | List II |
| 1. Light green to black | A: Copper carbonate |
| 2. White to yellow [heated state] | B: Hydrated Copper sulphate |
| 3. Blue to black | C: Copper nitrate |
| 4. Orange to green | D: Ammonium dichromate |
| 5. Blue to white | E: Zinc nitrate |
State which of the substance given below evolve oxygen gas on thermal decomposition.
Washing soda
State which of the substance given below evolve oxygen gas on thermal decomposition.
Trilead tetroxide
Give a balanced equation for the following reaction of synthesis involving the formation of:
An alkali – from a basic oxide – sodium oxide
Give a balanced equation for thermal decomposition of ammonium dichromate
Define a displacement reaction with a suitable example.
Differentiate between the following:
Synthesis reaction and a substitution reaction.
Differentiate between the following:
Thermal decomposition & thermal dissociation.
Differentiate between the following:
Decomposition reaction and a double decomposition reaction.
