Chemistry - Principles Related to Practical Chemistry
Exam Duration: 45 Mins Total Questions : 30
Xanthate formation test is basically related with
- (a)
aldehydes
- (b)
amines
- (c)
phenols
- (d)
alcohols
The one which gives ppt. with neutral FeCl3 is
- (a)
resorcinol
- (b)
vanillin
- (c)
benzonic acid
- (d)
All of these
One can separate the mixture of naphthalene and acetone by using
- (a)
NaHSO3
- (b)
HCl
- (c)
H2O
- (d)
NaOH
Which of the following compounds cannot used in preparation of iodoform?
- (a)
CH3CHO
- (b)
CH3COCH3
- (c)
HCHO
- (d)
2 - propanol
Which of the following substances is not used in the preparation of Mohr's salt?
- (a)
ferrous sulphate
- (b)
ammonium sulphate
- (c)
dil. sulphuric acid
- (d)
All are used
In the titration of oxalic acid vs potassium permanganate, potassium permanganate acts as
- (a)
external indicator
- (b)
self-indicator
- (c)
reductant
- (d)
Both (b) and (c)
The titration of Mohr's salt vs KMnO4 is an example of redox titration. In this titration, KMnO4 oxidises only ferrous salt to the ferric salt ( no effect on other ions) but we cannot use ferrous sulphate in place of Mohr's salt because
- (a)
it is less stable than Mohr's salt
- (b)
in air, it is oxidised to ferric sulphate
- (c)
in air, it loses water of crystallisation
- (d)
All of the above
A brown precipitate obtained by reaction of alkaline solution of Nessler's reagent and NH3 are due to the formation of
- (a)
mercuric hydroxide
- (b)
HgI42-
- (c)
Hg + Hg (NH2)I
- (d)
iodine of Millon's base
Sulphide insoluble in dil. HNO3 is
- (a)
HgS
- (b)
Bi2S3
- (c)
ZnS
- (d)
PbS
Identify the incorrect statement about Al2(SO4)3
- (a)
It is a white salt
- (b)
on adding NaOH solution to its aqueous solution, a precipitate is formed which get dissolve in excess of NaOH solution
- (c)
with lead acetate solution also, it gives a ppt.
- (d)
with silver nitrate, its aqueous solution gives a ppt.
Among the following pairs, the pair of salts gives yellow precipitate separately with aqueous solution of BaBr2 is
- (a)
Na2CO3, AgNO3
- (b)
K2SO4, K2CrO4
- (c)
K2SO4, AgNO3
- (d)
AgNO3, K2CrO4
Which of the following salts is soluble both in water and alcohol?
- (a)
AgCl
- (b)
AgBr
- (c)
Agl
- (d)
AgNO3
Which pair of ions gives ppt. when their dilute aqueous solutions are mixed?
- (a)
\(CO_3^{2-}, NH_4^+\)
- (b)
\(SO_3^{2-}, Na^+\)
- (c)
\(PO_4^{3-}, Fe^{3+}\)
- (d)
\(Na^{+}, S^{2-}\)
On passing a gas A through water, a saturated solution is formed. This solution on treating with AgNO3 gives a white ppt. And it also dissolves Mg ribbon with the evolution of a colourless gas B. Identify A and B
- (a)
A=Cl2 , B=H2
- (b)
A=H2 , B=Cl2
- (c)
A=CO2 , B=Cl2
- (d)
A=Cl2 , B=CO2
Sulphate insoluble in water is
- (a)
magnesium sulphate
- (b)
copper (II) sulphate
- (c)
silver (I) sulphate
- (d)
lead (II) sulphate
The salt which will not produce any gas with dil. H2SO4 is
- (a)
strontium nitrate
- (b)
calcium oxalate
- (c)
sodium nitrite
- (d)
Both (a) and (b)
The compound which is formed in the borax bead test of Cu2+ ion in oxidising flame is
- (a)
Cu(BO2)2
- (b)
CuBO2
- (c)
Cu
- (d)
None of these
Which is not a preliminary test used for the detection of \(NO_3^-\) ions?
- (a)
Borax bead test
- (b)
Flame test
- (c)
Permanganate test
- (d)
Brown ring test
When H2S is passed with HCl, the metal ion precipitated is
- (a)
Zn2+
- (b)
Mn2+
- (c)
Ni2+
- (d)
Cd2+
Which of the following on reaction with NaOH and Na2O3 gives yellow colour?
- (a)
Cr(OH)3
- (b)
Al(OH)3
- (c)
Zn(OH)3
- (d)
None of these
[A] + H2SO4 \(\rightarrow\) [B], a colourless gas having irritating smell
[B] + K2Cr2O7 + H2SO4 \(\rightarrow\) green solution
[A] and [B] are
- (a)
\(Cl^-,HCl\)
- (b)
\(CO_3^{2-}-,CO_2\)
- (c)
\(SO_3^{2-}-,SO_2\)
- (d)
\(S^{2-},H_2S\)
Ki solution identifies
- (a)
Cu2+
- (b)
Pb2+
- (c)
Sr2+
- (d)
Hg22+
Potassium ferrocyanide is useful in detection of
- (a)
Cu2+ ions
- (b)
Ca2+ ions
- (c)
Cd2+ ions
- (d)
Fe3+ ions
Diphenylamine reagent gives a deep blue colour with a solution which contains
- (a)
Sn2+
- (b)
Fe2+
- (c)
NO3-
- (d)
Cl-
On dilution of a salt solution in HCl with water, it turns milky due to the presence of
- (a)
Bi
- (b)
Al
- (c)
Ca
- (d)
Zn
Which of the following does not give flame test?
- (a)
Ba2+
- (b)
Mg2+
- (c)
Sr2+
- (d)
Ca2+
Which of the following hydroxides is/are soluble in excess of NaOH?
- (a)
Cr(OH)3
- (b)
Ca(OH)2
- (c)
Zn(OH)2
- (d)
Fe(OH)3
If Fe3+ and Cr3+ both are present in group III of qualitative analysis, then distinction can be made by
- (a)
addition of NH4Cl, when only Fe(OH)3 is precipitated.
- (b)
addition of NH4OH in presence of NH4 Cl when Cr(OH) and Fe(OH)3 both are precipitated and on adding Br2 water and NaOH, Cr(OH)3 dissolves
- (c)
precipitate of Cr(OH)3 and Fe(OH)3 as obtained in (b) are treated with conc. HCl, when only Fe(OH)3 dissolves
- (d)
Both (b) and (c)