The oxidation state of chromium in the final product formed by the reaction between KI and acidified potassium dichromate solution will be:
1. +2
2. +3
3. +4
4. +6
The lanthanide contraction is responsible for the fact that:
1. Zr and Y have about the same radius .
2. Zr and Zn have the same oxidation state.
3. Zr and Hf have about the same atomic radius .
4. Zr and Nb have a similar oxidation state.
Actinoids show a greater number of oxidation states than lanthanoids because:
1. | 4f- orbitals are more diffused than 5f-orbitals |
2. | Lesser energy difference between 5f, and 6d orbitals than between 4f, and 5d orbitals |
3. | More energy difference between 5f, and 6d orbitals than between 4f, and 5d orbitals |
4. | More reactive nature of the actinoids than the lanthanoids. |
Match the following characteristics to the appropriate metal:
Column I - Aspects | Column II - Metal | ||
(a) | The metal which reveals the maximum number of oxidation states | (i) | Scandium |
(b) | The metal although placed in 3d block is considered not as a transition element | (ii) | Copper |
(c) | The metal which does not exhibit variable oxidation states | (iii) | Manganese |
(d) | The metal which in +1 oxidation state in aqueous solution undergoes disproportionation | (iv) | Zinc |
Select the correct option :
(a) | (b) | (c) | (d) | |
1. | (i) | (iv) | (ii) | (iii) |
2. | (iii) | (iv) | (i) | (ii) |
3. | (iii) | (i) | (iv) | (ii) |
4. | (ii) | (iv) | (i) | (iii) |
The calculated spin-only magnetic moment of Cr2+ ion is:
1. | 4.90 BM | 2. | 5.92 BM |
3. | 2.84 BM | 4. | 3.87 BM |
Urea reacts with water to form A, which decomposes to form B. When B is passed through (aq), a deep blue-colored solution C is formed
The formula of C is:
2.
3.
4.
The incorrect statement among the following is:
1. | Zirconium and Hofnium have identical radii of 160 pm and 159 pm, respectively, as a consequence of lanthanoid contraction. |
2. | Lanthanoids reveal only a +3 oxidation state. |
3. | Lanthanoid ions, other than the f0 type and the f14 type, are all paramagnetic. |
4. | The overall decrease in atomic and ionic radii from lanthanum to lutetium is called lanthanoid contraction. |
What is produced when excessive diluted nitric acid is combined with potassium chromate?
1. Cr2O72- and H2O
2. Cr3+ and Cr2O72-
3. CrO42-
4. Cr2O42-
The magnetic moment of an Mn2+ ion is equal to:
1. | 5.92 BM | 2. | 2.80 BM |
3. | 8.95 BM | 4. | 3.90 BM |
Which of the following has the highest negative standard electrode potential ?
1. Ti
2. Cu
3. Mn
4. Zn