Zinc dissolve in an excess of NaOH because of the formation of:
1. ZnO
2. Zn(OH)2
3. NaZn(OH)3
4. Na2ZnO2
When excess of SnCl2 is added to HgCl2, the substance formed is
1. Hg2Cl2
2. Sn
3. Hg
4. Cl2
The oxidation number is changed in which of the following case
1. SO2 gas is passed into
2. Aqueous solution of is acidified
3. is dissolved in NaOH
4. solution is made alkaline
Which of the following elements form stable dinuclear ions
1. Zn
2. Cd
3. Hg
4. Fe
The correct electronic configuration of Ti(Z=22 atom) is
(1)
(2)
(3)
(4)
The correct statement regarding colour of Zn2+, Ni2+and Cr3+among the following is:
1. | Only Zn2+ is Colourless and Ni2+and Cr3+ are coloured |
2. | All these are colourless |
3. | All these are coloured |
4. | Only Ni2+ is coloured and Zn2+ and Cr3+ are colourless. |
The incorrect statement regarding the transition metals is:
1. | They are malleable and ductile. |
2. | They have high melting and boiling points. |
3. | They crystallise with body-centered cubic and hexagonal close-packed structure only. |
4. | They show variable oxidation states although not always. |
Assertion: Transition metals have high boiling points and high enthalpy of atomization.
Reason: The transition metals occur in bcc, hcp or ccp structures charcterstics of metals.
1. Both assertion and reason are true and the reason is the correct explanation of the assertion
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion
3. Assertion is true but reason is false
4. Both assertion and reason are false
Assertion: Zn, Cd and Hg are normally not considered transition metals.
Reason: d-orbitals in above elements are completely filled, hence above metals do not show the general charcterstic properties of the transition elements.
Assertion :A transition metal forms alloy with other transition metal easily.
Reason: The transition metals have similar electronic configuration,nearly equal radii and exhibit similar packing in their lattices.