Advertisements
Advertisements
प्रश्न
Why is freshly prepared ferrous sulphate solution used in the ring test?
उत्तर
Freshly prepared ferrous sulphate solution is used in the ring test otherwise. Ferrous sulphate undergoes aerial oxidation and converts to ferric sulphate.
APPEARS IN
संबंधित प्रश्न
How will you prepare the following from nitric acid?
copper nitrate
The chemical used in the brown ring test is ______.
The action of heat on the blue crystalline solid X gives a reddish brown gas Y, a gas which re-lights a glowing splint and leaves a black residue. When gas Z, which has a rotten egg smell, is passed through a solution of X, a black ppt. is formed.
- Identify X, Y and Z.
- Write the equation for action of heat on X.
- Write the equation between solution X and gas Z.
Complete and balance the following equation:
Cu + HNO3 → NO2 + ________+ _________
Explain, why only all glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.
Why should the temperature of the reaction mixture of nitric acid not be allowed to rise above 200oC?
Explain the following :
An all glass apparatus is used in the laboratory preparation of nitric acid.
X, Y, and Z are three crystalline solids that are soluble in water and have common anion.
To help you to identify X, Y and Z, you are provided with the following experimental observations. Copy and complete the corresponding inferences in (a) to (e).
- A reddish-brown gas is obtained when X, Y, and Z are separately warmed with concentrated sulphuric acid and copper turning added to the mixture.
INFERENCE 1: The common anion is the ______ ion. - When X is heated, it melts and gives off only one gas which re-lights a glowing splint.
INFERENCE 2: The cation in X is either ______ or ______. - The action of heat on Y produces a reddish-brown gas and yellow residue which fuses with a glass of the test tube.
INFERENCE 3: The metal ion present in Y is the ______ ion. - When Z is heated, it leaves no residue. Warming Z with sodium hydroxide solution liberates a gas which turns moist red litmus paper blue.
INFERENCE 4: Z contains the ______ cation. - Write the equations for the following reactions:
- X and concentrated sulphuric acid (below 200°C). (One equation only for either of the cations given in INFERENCE 2)
- The action of heat on Y.
- Concentrated nitric acid is added to copper turnings kept in a beaker.
Explain why nitric acid is kept in a reagent bottle for a long time.
What is the property of nitric acid which allows it to react with copper?
