Welcome to your P & C of OC - 4
1.
Potassium is not used in Lassaigne’s test because it
2.
Fresh FeSO4 is compulsory in nitrogen test because old FeSO4
3.
Sodium extract must be
4.
Sulphur is converted into which ionic species in Lassaigne’s test?
5.
Why halogen test is done after acidifying extract?
6.
Sulphur is detected by sodium nitroprusside test due to formation of
7.
Limewater turns milky due to formation of
8.
Thiophene dissolves in conc. H2SO4 due to
9.
Nitrogen detection gives Prussian blue colour due to formation of
10.
CO2 evolution confirms presence of
11.
Which precipitate dissolves in NH3?
12.
Detection of elements is called
13.
Which compound does NOT give positive Lassaigne test for nitrogen?
14.
Nitrogen in organic compound is converted into which compound during sodium fusion?
15.
Halogens are detected using
16.
Absolute alcohol is separated using
17.
Prussian blue colour disappears if
18.
Which halogen is not detected by Lassaigne’s test?
19.
Which reaction forms NaCN in fusion?
20.
Benzene is separated from thiophene using
21.
Gas-liquid chromatography mobile phase is
22.
Purpose of fusing organic compound with sodium in Lassaigne’s test is to convert elements into
23.
Lead acetate test for sulphur gives
24.
Phenol is separated from acids using
25.
Which compound gives false negative nitrogen test?
26.
Halogens are detected in Lassaigne’s test in the form of
27.
Lassaigne’s extract is
28.
Chromatography separates substances based on
29.
Hoffmann’s method separates amines using
30.
Why lithium is not used in Lassaigne’s test?
31.
Carbon detection test fails if
32.
When both nitrogen and sulphur are present, which compound is formed?
33.
Which element cannot be detected directly in organic compounds?
34.
Carbon detection is based on formation of
35.
Deep blue colour in nitrogen test confirms formation of
36.
Halogen test is done after boiling sodium extract with
37.
Which halogen gives yellow precipitate with AgNO3?
38.
Hydrogen detection is confirmed by
40.
Which reagent is used for carbon and hydrogen detection?
41.
Chromatography is useful when substance is present in
42.
Hinsberg reagent is used to separate
43.
Order of solubility of AgX in NH3 is
44.
Which compound interferes in nitrogen detection giving false result?
45.
Which compound gives positive test for both N and S?
