Assertion : Anhydrous copper(II) chloride is a covalent while anhydrous copper(II)fluoride is ionic in nature.
Reason: In halides of transition metals, the ionic character decreases with increase in atomic mass of the halogen.
Assertion: Eo for Mn3+/Mn2+ couple is more positive than for Fe3+/Fe2+.
Reason: Mn3+ has d4 configuration and Fe3+ has a d5 configuration.
Assertion: Transition metals exhibit higher enthalpies of atomization.
Reason: The atoms of transition metals are held together by strong metallic bonds.
Assertion : The transition elements form interstitial compounds.
Reason: Steel and cast iron are hard due to the formation of an interstitial compound with carbon.
When iron becomes passive by "X", it is due to the formation of "Y". X and Y, respectively, are:
1. Dil. HCl,
2. 80% Conc. ,
3. Conc. ,
4. Conc. HCl,
When KMnO4 solution is added to hot oxalic acid solution, the decolorization is slow in the beginning but becomes instantaneous after some time. This is because :
1. acts as auto catalyst.
2. is formed.
3. Reaction is exothermic.
4. catalyses the reaction.
Which of the following statements is false?
1. | MnO2 dissolves in conc. HCl, but does not form Mn4+ ions. |
2. | oxidizes hot concentrated liberating oxygen. |
3. | is formed when infused KOH is oxidized by air, , or |
4. | The decomposition of acidic is not catalyzed by sunlight. |
The addition of non-metals like B and C to the interstitial sites of a transition metal increases
1. Ductility
2. Melting Point
3. Shining
4. Conductivity
Which of the following metals does not form amalgam?
1. Fe
2. Au
3. Zn
4. Ag
The element of the first transition series having lowest oxidation potential value is -
1. Mn
2. Fe
3. Ni
4. Cu