Regents Chemistry Test Preparation Practice Voltaic Cell

What occurs at one of the electrodes in both an electrolytic cell and a voltaic cell?*

(1) Oxidation occurs as electrons are gained at the cathode.

(2) Oxidation occurs as electrons are lost at the anode.

(3) Reduction occurs as electrons are gained at the anode.

(4) Reduction occurs as electrons are lost at the cathode.

In an operating voltaic cell, reduction occurs*

(1) at the anode

(2) at the cathode

(3) in the salt bridge

(4) in the wire

An electrolytic cell differs from a voltaic cell because an electrolytic cell*

(1) generates its own energy from a spontaneous physical reaction

(2) generates its own energy from a nonsponta- neous physical reaction

(3) requires an outside energy source for a spontaneous chemical reaction to occur

(4) requires an outside energy source for a nonspontaneous chemical reaction to occur

Which change occurs at the anode in an operating electrochemical cell?*

(1) gain of protons

(2) gain of electrons

(3) loss of protons

(4) loss of electrons

Which reaction occurs at the cathode in an electrochemical cell?*

(1) combustion

(2) neutralization

(3) oxidation

(4) reduction

Which term identifies the half-reaction that occurs at the anode of an operating electro- chemical cell?*

(1) oxidation

(2) reduction

(3) neutralization

(4) transmutation

At which electrode does oxidation occur in a voltaic cell and in an electrolytic cell?*

(1) the anode in a voltaic cell and the cathode in an electrolytic cell

(2) the cathode in a voltaic cell and the anode in an electrolytic cell

(3) the anode in both a voltaic cell and an electrolytic cell

(4) the cathode in both a voltaic cell and an electrolytic cell

Where do reduction and oxidation occur in an electrolytic cell?*

(1) Both occur at the anode.

(2) Both occur at the cathode.

(3) Reduction occurs at the anode, and oxidation occurs at the cathode.

(4) Reduction occurs at the cathode, and oxidation occurs at the anode.

Which reaction occurs at the anode of an electrochemical cell?*

(1) oxidation

(2) reduction

(3) neutralization

(4) transmutation

Which reaction occurs at the anode in an electrochemical cell?*

(1) oxidation

(2) reduction

(3) combustion

(4) substitution

Base your answers to questions 11 on the information below.

The diagram below represents an operating electrolytic cell used to plate silver onto a nickel key. As the cell operates, oxidation occurs at the silver electrode and the mass of the silver electrode decreases.

oxidation-reduction, electrochemical-cell, voltaic-cell fig: chem12012-exam_g16.png

Identify the cathode in the cell.*

Base your answers to questions 12 on the information below and on your knowledge of chemistry.

A student constructs an electrochemical cell. A diagram of the operating cell and the unbalanced ionic equation representing the reaction occurring in the cell are shown below.

The blue color of the solution in the copper half-cell indicates the presence of Cu²⁺ ions. The student observes that the blue color becomes less intense as the cell operates.

oxidation-reduction, electrochemical-cell, voltaic-cell, oxidation-reduction, electrochemical-cell, voltaic-cell fig: chem12019-exam_g14.png

Identify the type of electrochemical cell represented by the diagram.*

Base your answers to questions 13 on the information below and on your knowledge of chemistry.

An operating voltaic cell has magnesium and silver electrodes. The cell and the ionic equation representing the reaction that occurs in the cell are shown below.

oxidation-reduction, electrochemical-cell, voltaic-cell, oxidation-reduction, oxidation-reduction-(redox)-reaction fig: chem62019-exam_g17.png

Explain, in terms of electrical energy, how electrolysis reactions differ from voltaic cell reactions.*

Base your answers to questions 14 on the information below and on your knowledge of chemistry.

Electroplating is an electrolytic process that can be used to coat metal objects with a less reactive metal. The diagram below shows an electroplating cell that includes a power source connected to a copper rod and a bracelet made from a different metal. The rod and bracelet are in an aqueous copper(II) sulfate solution.

oxidation-reduction, electrochemical-cell, voltaic-cell, oxidation-reduction, oxidation-reduction-(redox)-reaction fig: chem82023-exam_g22.png

Identify the electrode that attracts the Cu²⁺ ions as the cell operates. [1]*

Base your answers to questions 15 on the information below and on your knowledge of chemistry.

A student made a copper bracelet by hammering a small copper bar into the desired shape. The bracelet has a mass of 30.1 grams and was at a temperature of 21°C in the classroom. After the student wore the bracelet, the bracelet reached a temperature of 33°C. Later, the student removed the bracelet and placed it on a desk at home, where it cooled from 33°C to 19°C. The specific heat capacity of copper is 0.385 J/g•K.

Explain, in terms of chemical activity, why copper is a better choice than iron to make the bracelet.*