In the blast furnace, iron ore (Fe$_2$O$_3$) is reduced to iron in several steps.
At 900-1500 K, the following reaction occurs:
FeO + CO → Fe + CO$_2$
This is the reduction of FeO (wustite) by carbon monoxide to produce iron and carbon dioxide.
Samples of four metals A, B, C, and D were added one by one to the following solutions. The results obtained were tabulated as follows:
Use the table above to answer the following questions about metals A, B, C, and D:
(i) Which is the least reactive metal?
(ii) What would be observed if C is added to a solution of copper sulphate?
(iii) Arrange the metals A, B, C, and D in the order of their decreasing reactivity.
Which of the following are ambident nucleophiles?
[A.] CN$^{\,-}$
[B.] CH$_{3}$COO$^{\,-}$
[C.] NO$_{2}^{\,-}$
[D.] CH$_{3}$O$^{\,-}$
[E.] NH$_{3}$
Identify the anomers from the following.

The standard Gibbs free energy change \( \Delta G^\circ \) of a cell reaction is \(-301 { kJ/mol}\). What is \( E^\circ \) in volts?
(Given: \( F = 96500 { C/mol}\), \( n = 2 \))