The spontaneous reaction that occurs when the cell in the picture operates is as follows: 2Ag+ + Cd(s) à 2 Ag(s) + Cd2+ (A) Voltage increases. (B) Voltage decreases but remains > zero. (C) Voltage becomes zero and remains at zero. (D) No change in voltage occurs. (E) Direction of voltage change cannot be predicted without additional information.

The question is incomplete, the remaining part of the question is

Which of the above occurs for each of the following circumstances?

A 50-milliliter sample of a 2-molar Cd(NO3)2 solution is added to the left beaker.

Voltage decreases but remains > zero.

Explanation:

Given the balanced redox reaction equation:

2Ag^+(aq) + Cd(s) > 2 Ag(s) + Cd^2+(aq)

Concentration affects the cell voltage according to Nernst equation. Change in concentration must lead to a change in cell Voltage.

As the concentration of the Cd(NO3)2 solution is increased, voltage decreases because of the increase in the concentration values but voltages remains above zero.

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.