Electrochemistry, Redox Reactions, and Functions of Money

Vocabulary review covering electrochemical concepts, cell reactions, the reactivity series, redox processes, ions, and economic functions of money.

Electrochemistry

The branch of chemistry that deals with the study of processes that produce electricity through chemical reactions and use electricity to bring about chemical reactions.

Electrochemical cells

Devices that make processes that produce electricity through chemical reactions and use electricity to bring about chemical reactions possible.

Reactivity series

The series in which metals are arranged in decreasing order of their chemical reactivity (starting with potassium, sodium, calcium, magnesium, aluminium, down to gold).

Reducing agent

The substance that causes reduction.

Cathode reaction (in a Zn-Cu galvanic cell)

The reduction reaction occurring at the cathode, represented as $Cu^{2+} + 2e^- \rightarrow Cu$.

Cell reaction / Redox reaction (in a Zn-Cu cell)

The combined electrochemical reaction represented as $Zn + Cu^{2+} \rightarrow Zn^{2+} + Cu$.

Electron flow in a Zn-Cu galvanic cell

The direction in which electrons travel, moving from the $Zn$ anode to the $Cu$ cathode to produce electric current.

Voltage comparison: Al-Cu vs. Zn-Cu cell

The $Al\text{-}Cu$ galvanic cell generates a higher voltage than the $Zn\text{-}Cu$ cell because the tendency of aluminium to get oxidised in a redox reaction is greater than that of zinc.

Ions

Charged atoms.

Cation

A positively charged (+ve) ion formed by the removal of electrons.

Anion

A negatively charged (-ve) ion formed by the gain of electrons.

Oxidation

The removal of electrons, which leads to the formation of a cation.

Reduction

The gain of electrons, which leads to the formation of an anion.

Measure of value

A function of money wherein the value of all goods can be expressed in monetary terms, making it easy to compare the value of goods.

Purchasing power of money

The value of money, which decreases when the prices of goods increase and increases when the prices of goods decrease.

Store of value

A function of money that enables the value of any good to be stored in the form of money, converted, and utilized in the future.

Deferred payments

A function of money that allows measuring the value of borrowing and lending, providing support for short-term and long-term business transactions.