Deep blue CusO4·5H2O is converted to a bluish white salt at 100°C. At 250°C and 750°C it is then transformed to a white powder and black material respectively. Identify the salts.
Two equilibria, AB A +B. are simultaneously maintained in a solution with equilibrium constants, K1 and K2 respectively. The ratio of [A+] to [AB] in the solution is
directly proportional to [B-]
inversely proportional to [B-]
directly proportional to the square of [B-]
inversely proportional to the square of [B-]
The colour of the soltuion/ precipitate obtained in the elemental analysis of an organic compound and the molecule/ion responsible for the colour are given below. Choose the incorrectly matched pair.
Prussian blue - Fe4[Fe(CN)6]3.xH2O
Yellow - (NH4)2MoO4
Violet colour - [Fe(CN)5NOS]4-
Blood red colour - [Fe(SCN)]2+
In the following equilibrium reaction,
2A B + C
the equilibrium concentration of A, B and C are 1 × 10-3 M, 2 × 10-3 M and 3 × 10-3 M respectively at 300 K. The value of Kc for this equilibrium at the same temperature is
6
36
In the reaction H2S+ H2O2 → S+ 2H2O
H2S is an acid and H2O2 is a base
H2S is a base and H2O2 is an acid
H2S is an oxidising agent and H2O2 is a reducing agent
H2S is an reducing agent and H2O2 is a oxidising agent
The solubility product (Ks) of the following compounds are given at 25°C
Compounds |
Ksp |
AgCl | 1.1 × 10-10 |
AgI | 1.0 × 10-16 |
PbCrO4 | 4.0 × 10-14 |
Ag2CO3 | 8.0 × 10-12 |
The most soluble and least soluble compounds are
AgCl and PbCrO4
AgI and Ag2CO3
AgCl and Ag2CO5
Ag2CO3 and AgI
D.
Ag2CO3 and AgI
The most soluble and least soluble compounds are Ag2CO3 and AgI.
(i) AgI
Ksp = [Ag+][I-]
= s × s = s2
Ksp = s2 = 1.0 × 10-16
or, s = 1.0 × 10-8 mol L-1
(ii) Ag2CO3
Ksp = [Ag+]2[CO]
= (2s)2 × s = 4s3
Ksp = 4s3 = 8.0 × 10-12
or, s = 1.26 × 10-4 mol L-1
The dissociation constant of acetic acid Ka is 1.74 × 10-5 at 298 K. The pH of a solution of 0.1 M acetic acid is :
2.88
3.6
4.0
1.0
0.365g of HCl gas was passed through 100 cm3 of 0.2 M NaOH solution. The pH of the resulting solution would be :
13
9
8
5