Assertion : Cuprous ion is colourless whereas cupric ion produces blue colour in solution.
Reason : Cuprous ion has unpaired electrons while cupric ion does not.
Assertion : Ammonical silver nitrate converts glucose to gluconic acid and metallic silver is precipitated.
Reason : Glucose acts as a weak reducing agent.
Assertion: To a solution of potassium chromate if a strong acid is added it changes its colour from yellow to orange.
Reason : The colour change is due to the oxidation of potassium chromate.
Which one of the following statements is not correct
1. Nickel forms Ni(CO)4
2. All the transition metals form mono-metallic carbonyls
3. Carbonyl are formed by transition metals
4. Transition metals form complexes
Which of the following pairs of compounds are more stable
(A)
(B) NiCl4, PtCl4
(C)
(D) PtCl2, NiCl2
The radius of La3+ (atomic number of La=57) is 1.06 . Which one of the following given values will be closest to the radius of Lu3+ (atomic number of Lu =71)
(1) 1.60
(2) 1.40
(3)1.96
(4)0.85
Match the underlined atom in Column A with oxidation number in Column B.
A B
(a) [Fe(CN)5O]2- 0(I)
(b) [Ag(CN)2]- 3(II)
(c) [Cr(en)3]3+ 1(III)
(d) Ni(CO)4 2(IV)
a b c d
(A) I II III IV
(B) II III IV I
(C) IV III II I
(D) II III I IV
By calculating Eo value of the following reaction,which one of the following reaction are spontaneous.
Given
(A) Only d
(B) Only b
(C) Both c & d
(D) Both a & c
Which of the following has maximum number of unpaired electrons?
(1) Fe2+
(2) Fe3+
(3) Co3+
(4) Co2+
The atomc number of potassium is 19 & that of manganese is 25. Although the colour of MnO4- is dark violet yet the K+ is colourless.This is due to the fact that
(1) Mn is a transition element; while K+ is not
(2) [MnO4]- is negatively charged; while K+ has a positive charge.
(3) The effective atomic number of Mn in [MnO4]- is 26; while for K+ , the atomic number s 18
(4) The Mn in a high positive oxidation state allow charge transfer transitions.