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.

Heating of Ag with dil. HNO₃ give

1. NO

2. NO₂

3. N₂O

4. N₂O₃

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 $C{r}_2{O}_7^{2-}/H^{+}$

2. Aqueous solution of $Cr{O}_4^{2-}$ is acidified

3. $Cr{O}_{2}C{l}_2$ is dissolved in NaOH

4. $C{r}_2{O}_7^{2-}$ 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) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^2$

(2) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{2}4p^6$

(3) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^4$

(4) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^2$

The correct statement regarding colour of Zn²⁺, Ni²⁺and Cr³⁺among the following is:

The incorrect statement regarding the transition metals is:

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