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प्रश्न
What is Nessler’s reagent?
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उत्तर
- Nessler's reagent is a solution of mercury(II) iodide (HgI2) in potassium iodide (KI) and potassium hydroxide (KOH) named after the German chemist Julius Nessler.
- Nessler’s reagent is an alkaline solution of K2 HgI4.
- It is used in testing for ammonia, with which it forms a brown colouration or precipitate.
\[\ce{NH3 + 2[HgI4]^2- + 4OH^- → HgO.Hg(NH2) + 7I^- + 3H2O}\]
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Low ammonia: Yellow coloration
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High ammonia: Reddish-brown precipitate
This color change confirms the presence of ammonia.
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संबंधित प्रश्न
Describe the laboratory method of preparation of ammonia
What is the action of the following reagents on ammonia :
Nessler's reagent
Mention the conditions required to maximise the yield of ammonia.
How does ammonia react with a solution of Cu2+?
What happens when (NH4)2Cr2O7 is heated? Write the equations.
What is the action of Na Metal on ammonia?
What is the action of the following reagents on ammonia :
Sodium metal
In laboratory ammonia is prepared by heating:
Ammonia has a higher boiling point and is less volatile because of ____________.
Which compound is used as the cooling liquid in refrigerators?
Ammonia act as a Lewis base because nitrogen has ____________.
On heating ammonium dichromate and barium azide separately we get ______.
In Haber’s process for the manufacture of NH3:
Ammonia on reaction with hypochlorite anion can form:
The shape of ammonia molecule is ____________.
When ammonia is heated with cupric oxide, a molecule of ammonia will ____________.
Liquid ammonia bottles are opened after cooling them in ice for some time. It is because liquid NH3 ____________.
Ammonia is generally manufactured for fertilizers by the reaction:
Which one of the following is not a use of ammonia?
In qualitative analysis when \[\ce{H2S}\] is passed through an aqueous solution of salt acidified with dil. \[\ce{HCl}\], a black precipitate is obtained. On boiling the precipitate with dil. \[\ce{HNO3}\], it forms a solution of blue colour. Addition of excess of aqueous solution of ammonia to this solution gives ______.
A brown ring is formed in the ring test for \[\ce{NO3^{-}}\] ion. It is due to the formation of ______.
In the preparation of HNO3, we get NO gas by catalytic oxidation of ammonia. The moles of NO produced by the oxidation of two moles of NH3 will be ______.
What happens when reactions:
Benzylchloride is treated with ammonia followed by the reaction with Chloromethane.
