Consider following compounds and decide as to which of the following statements are true ?
(1) (II) gives no reaction with Na metal, however, 1 mole of (IV) on reaction with Na metal will liberate 22.4 litres of H2 gas at STP
(2) (I) will give brisk effervescence on addition of NaHCO3 but will not bring any change in the colour of Br2 water
(3) (III) Iiberates H2 gas with Na metal, gives white precipitate with Tollen's reagent but does not respond towards lucas reagent or 2, 4–DNP test.
(4) (IV) gives turbidity with anhydrous ZnCI2
The Prussian blue colour obtained during the test of nitrogen by Lassaigne's test is due to the formation of-
1. | Fe4[Fe(CN)6]3 | 2. | Na3[Fe(CN)6] |
3. | Fe(CN)3 | 4. | Na4[Fe(CN)5NOS] |
A compound that does not give a positive test in Lassaigne’s test for nitrogen is:
1. Urea
2. Hydrazine
3. Azobenzene
4. Phenylhydrazine
The silver sulphate solution is used to separate:
1. nitrate and bromide
2. nitrate and chlorate
3. bromide and iodide
4. nitrate and nitrite
Soda extract is prepared by-
1. Fusing soda and mixture of hydrocarbons, and then extracted with water
2. Dissolving NaHCO3 and mixture of hydrocarbons in dil. HCl
3. Boiling Na2CO3 and mixture of hydrocarbons in dil. HCl
4. Boiling Na2CO3 and mixture of hydrocarbons in distilled water
The Lassaigne's extract is boiled with a concentration HNO3 while testing for halogens. By doing so it
1. Helps in the precipitation of AgCl
2. Increases the solubility product of AgCl
3. Increases the concentration of NO3- ions
4. Decomposes Na2S and NaCN, if formed.
Assertion (A): | CCl4 doesn't give precipitate of AgCl on heating with AgNO3. |
Reason (R): | CCl4 is a non-polar molecule. |
1. | (A) is true and (R) is the correct explanation of (A). |
2. | (A) is true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false |
In the Lassaigne’s test for nitrogen in an organic compound, the Prussian blue colour is obtained due to the formation of-
Lassaigne's test can detect:
1. Nitrogen, Sulphur, Halogens
2. Nitrogen, Cyanides, Sulphur
3. Sodium, Sulphur, Halogens, Phosphorus
4. Nitrogen, Sulphur, Halogens, Phosphorus
Nitric acid is added to sodium extract before adding silver nitrate for testing halogens because:
1. Nitric acid reduces sulphide
2. Nitric acid decomposes NaCN and Na2S
3. Nitric acid oxidises the organic compound
4. Nitric acid acts as a dehydrating agent