Question

The reactants of two chemical reactions are shown.

Reaction 1: HCl and NaOH
Reaction 2: Cu and AgNO3

Which reaction is likely to be a redox reaction?
A) Reaction 1, because hydrogen and hydroxide atoms will be formed.
B) Reaction 1, because all ions formed will retain their electrostatic charges.
C) Reaction 2, because the electrostatic charge on copper ion will change.
D) Reaction 2, because the charges on each side of the equation will be unequal.

Answer 1

Answer: C

Explanation: I took the test and it was right

Answer 2

C)

Step-by-step explanation:

The first step is to write the whole reactions:

A)
`HCl~+~NaOH~->~H_2O~+~NaCl`

B)
`Cu~+~AgNO_3~->~Cu(NO_3)_2~+~Ag`

In A) reaction we will have an acid-base reaction (double replacement reaction). In this reaction, the oxidation number is the same for all atoms on both sides of the reaction.

In B) the oxidation number of Cu will change from zero to +2 and the oxidation number of Ag will change from +1 to zero. So, the Cu will be oxidized and the Ag will reduce. So, if we have a redox reaction for B) the charge must be equal on both sides.