Advertisements
Advertisements
Question
'A' is a blue coloured crystalline salt. On heating, it loses blue colour and to give 'B'. When water is added, 'B' gives back to 'A'. Identify A and B, write the equation.
Advertisements
Solution
Since ‘A’ is a blue coloured crystalline salt, it is CuSO4. 5H2O (Blue vitriol). On heating, it loses all five water molecules and becomes colourless anhydrous CuSO4.
\[\ce{\underset{\text{(A)}}{CuSO4.5H2O} ⇌[heating][cooling]\underset{\text{anhy. copper sulphate} Colourless (B)}{CuSO4 + 5H2O}}\]
When water is added ‘B’ gives back A.
APPEARS IN
RELATED QUESTIONS
Give two examples of Crystalline anhydrous substances.
What do you observe when Blue vitriol is heated?
Give the names and formulae of two substances
Anhydrous substance
What are drying or desiccating agents? Give examples.
What are hydrous substances? Explain with examples.
Complete the statement by filling the blank with the correct word from the option.
Hygroscopic substance absorb moisture from the atmosphere & _______their original state.
Differentiate between hydrated and anhydrous crystals with examples. State three defined changes that occur when hydrated copper sulphate is heated.
Select the correct answer from the choice given in the options.
An anhydrate of a heptahydrate salt _____.
Give a reason for the following:
Heating a hydrated copper sulphate crystal is deemed a chemical change.
Match the following
| 1. | Blue vitriol | CaSO4.2H2O |
| 2. | Gypsum | CaO |
| 3. | Deliquescence | CuSO4.5H2O |
| 4. | Hygroscopic | NaOH |
