Question

Determine whether each statement describes an anode or a cathode in a voltaic cell.

Where the reduction occurs Choose...

The positive terminal Choose...

Where electrons flow from Choose...

Where the oxidation occurs Choose...

Where electrons flow to Choose...

The negative terminal Choose...

Answer 1

1. Where the reduction occurs : Cathode

Cathode is source of electrons these electrons reduces cations to elements (usually metals)

Illustration : In a Zn /Cu voltic cell

Cu⁺² + 2e^- --> Cu(s)

copper ion (Cu⁺²) being positively  charged  gain electrons at cathode to give metallic copper

Addition of electron is called reduction. Therefore reduction occurs at anode

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2. Positive terminal is cathode The electrode at which electrons are received from the outer circuit. It has a positive charge and is know as (+) in the voltic cell diagrams

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3.Where the electron flows from Anode

Oxidation occurs at anode and the liberated electrons flows from anode to cathode through outer circuit.

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4. Where the oxidation occurs anode

The metal gives up electron to form charged species. This process is called oxidation. In a voltic cell of Zn /Cu

Zn ---> Zn⁺² +2e^-

Thus oxidation occurs at anode.

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5.The electrons flows to cathode

The electrons from the anode enter into the cathode through external circuit to cathode in voltic cell.

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6. The negative terminal is anode. Anode is the elctrode in an voltic cell where oxidation occurs. It sends electrons to the cathode through the outer circuit. It has a negative charge and is shown as (-) in a voltic cell diagram