271.

Point out the correct statement.

• Below 710$°$C, C is better reducing agent than CO

• Below 710°C, CO is better reducing agent than C

• Below 710$°$C, CO is an oxidising agent

• Below 710$°$C, CO, is a reducing agent

KMnO₄ reacts with ferrous sulphate according to the following equation,

Mn${\mathrm{O}}_4^{-}$ + 5Fe²⁺ + 8H^- $\to$Mn²⁺ + 2Fe³⁺ + 4H₂O

Here, 10 mL of 0.1M KMnO₄ is equivalent to

• 50 mL of 0.1 M FesO₄

• 20 mL of 0.1 M FesO₄

• 40 mL of 0.1 M FesO₄

• 30 mL of 0.1 M FeSO₄

Which of the following species do not show disproportionation on reaction?

ClO^-, Cl${\mathrm{O}}_2^{-}$ , Cl${\mathrm{O}}_3^{-}$ and Cl${\mathrm{O}}_4^{-}$

• Cl${\mathrm{O}}_4^{-}$

• Cl${\mathrm{O}}_4^{-}$

• ClO^-

• None of these

For the reaction,

NH₃ + OCl^- $\to$ N₂H₄ + Cl^-

occurring in basic medium, the coefficient of N₂H₄ in the balanced equation will be

• 1

• 2

• 3

• 4

The maximum oxidation state exhibited by actinide ions is

• +5

• +4

• +7

• +8

In an oxidation-reduction reaction, MnO${}_4^{-}$ ion is converted to Mn²⁺. What is the number of equivalents of KMnO₄ (mol. wt.= 158) present in 250 mL of 0.04 M KMnO₄ solution ?

• 0.02

• 0.05

• 0.04

• 0.07

Oxidation state of oxygen in F₂O is

• +1

• -1

• +2

• -2

Which of the following is wrong statement?

• Ni(CO)₄ has oxidation number +4 for Ni

• Ni(CO)₄ has zero oxidation number for Ni

• Ni is metal

• CO is gas

Consider a titration of potassium dichromate solution with acidified Mohr's salt solution using diphenyl amine as indicator. The number of moles of Mohr's Salt required per mole of dichromate is:

• 3

• 4

• 5

• 6

When MnO₂ is fused with KOH, a colouredcompound is formed. The product and its colour is:

• K₂MnO₄ , purple colour

• Mn₂O₃ , brown

• Mn₂O₄ , black

• KaMnO₄ , purple