Chemistry
When an ammonium salt is warmed with sodium hydroxide solution, a gas is evolved. State three ways in which you could identify this gas.
Answer
When an ammonium salt is warmed with sodium hydroxide solution, ammonia gas is evolved.
NH4Cl + NaOH ⟶ NaCl + H2O + NH3
Three ways in which ammonia gas can be identified is:
- It has a sharp characteristic odour.
- It turns:
- moist red litmus blue,
- moist turmeric paper brown,
- phenolphthalein solution pink.
- It gives dense white fumes with conc. hydrochloric acid.
NH3 + HCl ⟶ NH4Cl
Related Questions
Name:
(a) the gas which is prepared by Haber's process.
(b) two gases which give dense white fumes with ammonia.
(c) one salt of ammonia in each case which is used in:
(i) dry cell
(ii) explosives
(iii) medicine
(d) an acidic gas which reacts with a basic gas liberating a neutral gas
(e) a metallic chloride soluble in ammonium hydroxide
(f) the gas obtained when ammonia burns in an atmosphere of oxygen without any catalyst
(g) a nitride of a divalent metal which reacts with warm water liberating ammonia
(h) an amphoteric oxide reduced by the basic gas
(i) a white salt produced by an acidic gas and a basic gas
A gas 'A' reacts with another gas 'B' in the presence of a catalyst to give a colourless gas 'C'. The gas 'C' when comes in contact with air produces a brown gas 'D'. The solution of 'A' in water turns red litmus blue. Explain the observations.
When ammonium hydroxide is added to solution B, a pale blue precipitate is formed. This pale blue precipitate dissolves in excess ammonium hydroxide giving an inky blue solution. What is the cation (positive ion) present in solution B? What is the probable colour of solution B.
(i) Name the common refrigerant. How does it deplete ozone layer?
(ii) What is the alternative of chlorofluorocarbon carbon?
(iii) State the advantages and disadvantages of using ammonia as refrigerant?