Assuming complete ionization, same moles of which of the following compounds will require the least amount of acidified KMnO4 for complex oxidation?
1.
2.
3.
4.
Which of the following processes does not involve the oxidation of iron?
1. | Rusting of iron sheets |
2. | Decolourisation of blue CuSO4 solution by iron |
3. | Formation of Fe(CO)5 from Fe |
4. | Liberation of H2 from steam by iron at high temperature |
The pair of compounds that can exist together is:
1. FeCl3, SnCl2
2. HgCl, SnCl2
3. FeCl2, SnCl2
4. FeCl3, Kl
1. | Both Sc3+ and Zn2+ ions are colourless and form white compounds |
2. | In the case of Sc, 3d orbitals are partially filled but in Zn, these are fully filled. |
3. | The last electron is assumed to be added to the 4s level in the case of Zn |
4. | Both Sc and Zn do not exhibit variable oxidation states. |
Which of the following statements is false?
1. | On passing H2S through acidified K2Cr2O7 solution, a milky colour is observed. |
2. | Na2Cr2O7 is preferred over K2Cr2O7 in volumetric analysis. |
3. | K2Cr2O7 solution in an acidic medium is orange. |
4. | K2Cr2O7 solution becomes yellow in increasing the pH beyond 7 |
The catalytic activity of transition metals and their compounds is ascribed mainly to:
1. their unfilled d-orbitals
2. their ability to adopt variable oxidation states
3. their chemical reactivity
4. their magnetic behaviour
Which one of the following does not correctly represent the correct order of the property indicated against it?
1. | Ti3+< V3+< Cr3+< Mn3+: increasing magnetic moment |
2. | Ti < V < Cr < Mn : increasing melting point |
3. | Ti < V < Mn < Cr : increasing 2nd ionization enthalpy |
4. | Ti < V < Cr < Mn : increasing number of oxidation states |
Which of the following exhibits only a +3 oxidation state?
1. | Th | 2. | Ac |
3. | Pa | 4. | U |