The electrochemical series is a list of metals and non-metals arranged in order of their standard electrode potentials (reduction potentials) or their tendency to undergo reduction. It is also known as the activity series. The electrochemical series is a useful tool in predicting the outcome of redox reactions, especially in electrolytic cells and in electrochemical cells.
Metals at the top of the electrochemical series have a greater tendency to lose electrons and undergo oxidation than those at the bottom. Similarly, non-metals at the bottom of the series have a greater tendency to gain electrons and undergo reduction than those at the top.
The standard electrode potential of hydrogen is taken as the reference point and is assigned a value of 0.00 volts. Elements with a positive standard electrode potential have a greater tendency to be reduced and act as oxidizing agents, while elements with a negative standard electrode potential have a greater tendency to be oxidized and act as reducing agents.
Some examples of elements in the electrochemical series, in order from most to least reactive, include:
- Lithium
- Potassium
- Calcium
- Sodium
- Magnesium
- Aluminum
- Zinc
- Iron
- Lead
- Copper
- Silver
- Gold
Note that this is just a partial list and the order can vary depending on the conditions of the reaction.
What is Required Electrochemical series
The Required Electrochemical Series is a list of elements, ions or molecules arranged in order of their standard reduction potentials, which determines the feasibility and direction of redox reactions in electrolytic and electrochemical cells. Unlike the conventional electrochemical series, the required electrochemical series provides information on the reduction potentials of different species in a reaction and can be used to predict the outcome of complex redox reactions involving multiple species.
The standard reduction potential of a substance is a measure of its tendency to undergo reduction and is measured in volts. In the required electrochemical series, the species with the highest reduction potential is placed at the top of the list, while the species with the lowest reduction potential is placed at the bottom.
Some examples of species in the required electrochemical series include:
- F2 (fluorine gas)
- O2 (oxygen gas)
- H+ (hydrogen ion)
- Cu2+ (copper ion)
- Fe3+ (iron ion)
- Ag+ (silver ion)
- H2O2 (hydrogen peroxide)
- Sn2+ (tin ion)
- Zn2+ (zinc ion)
Note that this is just a partial list and the order can vary depending on the specific conditions of the reaction, such as pH, temperature, and concentration.
Reactivity series
In science, a reactivity series (or action series) is an experimental, determined, and primarily logical movement of a progression of metals, organized by their “reactivity” from most noteworthy to least. Summing up data about the responses of metals with acids and water, single dislodging responses and the extraction of metals from their ores is utilized.
Standard electrode potential (data page)
The data values of standard electrode potentials (E°) are given in the table below, in volts relative to the standard hydrogen electrode, and are for the following conditions:
- A temperature of 298.15 K (25.00 °C; 77.00 °F).
- An effective concentration of 1 mol/L for each aqueous species or a species in a mercury amalgam (an alloy of mercury with another metal).
- A partial pressure of 101.325 kPa (absolute) (1 atm, 1.01325 bar) for each gaseous reagent. This pressure is used because most literature data are still given for this value (1 atm) rather than for the current standard of 100 kPa (1 bar) presently considered in the standard state.
- An activity of unity for each pure solid, pure liquid, or for water (solvent). The relation in electrode potential of metals in saltwater (as electrolyte) is given in the galvanic series.
- Although many of the half cells are written for multiple-electron transfers, the tabulated potentials are for a single-electron transfer. All of the reactions should be divided by the stoichiometric coefficient for the electron to get the corresponding corrected reaction equation. For example, the equation Fe2+ + 2 e− ⇌ Fe(s) (–0.44 V) means that it requires 2 × 0.44 eV = 0.88 eV of energy to be absorbed (hence the minus sign) in order to create one neutral atom of Fe(s) from one Fe2+ ion and two electrons, or 0.44 eV per electron, which is 0.44 J/C of electrons, which is 0.44 V.
- After dividing by the number of electrons, the standard potential E° is related to the standard Gibbs free energy of formation ΔGf° by:
where F is the Faraday constant. For example, in the equation Fe2+ + 2 e− ⇌ Fe(s) (–0.44 V), the Gibbs energy required to create one neutral atom of Fe(s) from one Fe2+ ion and two electrons is 2 × 0.44 eV = 0.88 eV, or 84 895 J/mol of electrons, which is just the Gibbs energy of formation of an Fe2+ ion, since the energies of formation of e− and Fe(s) are both zero.
The Nernst equation will then give potentials at concentrations, pressures, and temperatures other than standard.
- Note that the table may lack consistency due to data from different sources. For example:
| Cu+ | + e− | ⇌ | Cu(s) | (E1 = +0.520 V) |
| Cu2+ | + 2 e− | ⇌ | Cu(s) | (E2 = +0.337 V) |
| Cu2+ | + e− | ⇌ | Cu+ | (E3 = +0.159 V) |
Calculating the potential using Gibbs free energy (E3 = 2E2 – E1) gives the potential for E3 as 0.154 V, not the experimental value of 0.159 V.
Nomenclature of Electrochemical series
The nomenclature of the electrochemical series is based on the standard electrode potential of each element, which is a measure of the voltage generated when the element is connected to a standard hydrogen electrode under standard conditions. The standard electrode potential of hydrogen is defined as 0 volts, and the electrode potential of other elements is expressed relative to hydrogen.
The electrochemical series is arranged in order of the standard electrode potential of each element, with the most reactive element at the top and the least reactive element at the bottom. The nomenclature of the electrochemical series usually includes the name of the element, its symbol, and its standard electrode potential in volts. For example, the electrochemical series starts with Lithium with a standard electrode potential of -3.05 volts, so it is written as Li(-3.05 V).
The standard electrode potentials of some common elements in the electrochemical series are:
- Lithium (Li): -3.05 V
- Sodium (Na): -2.71 V
- Magnesium (Mg): -2.37 V
- Aluminum (Al): -1.66 V
- Zinc (Zn): -0.76 V
- Iron (Fe): -0.44 V
- Copper (Cu): +0.34 V
- Silver (Ag): +0.80 V
- Gold (Au): +1.50 V
In addition, the nomenclature of the electrochemical series may include the oxidation state of the element, if applicable. For example, the electrochemical series includes both Fe2+ and Fe3+, with standard electrode potentials of -0.44 V and +0.77 V, respectively. These are written as Fe2+/Fe(-0.44 V) and Fe3+/Fe(+0.77 V), respectively.
Overall, the nomenclature of the electrochemical series provides a systematic way of organizing information about the relative reactivity of different elements in electrochemical reactions.
How is Required Electrochemical series
The required electrochemical series is a list of redox reactions arranged in order of the required potential for a given reaction to occur under specific conditions. To obtain the required electrochemical series, we need to consider the half-cell reactions involved in the redox reactions and their standard electrode potentials.
The required potential for a redox reaction to occur is the difference between the standard electrode potentials of the two half-reactions involved in the reaction. If the required potential is positive, the reaction is thermodynamically feasible, and the reactants will tend to form products spontaneously. If the required potential is negative, the reaction is not thermodynamically feasible, and an external voltage or energy input is required to drive the reaction.
To construct a required electrochemical series, we need to arrange a list of redox reactions in order of the required potential for each reaction to occur. This can be done by comparing the standard electrode potentials of the half-cell reactions involved in each reaction and calculating the required potential using the Nernst equation or other thermodynamic relationships.
The required electrochemical series can be useful in predicting the feasibility of redox reactions under specific conditions, such as temperature, pressure, pH, and concentration. It can also be used to rank the relative reactivity of different species in a redox reaction and to optimize electrochemical processes and devices.
Overall, the construction and application of the required electrochemical series involve a combination of experimental measurements, theoretical calculations, and data analysis, and its accuracy and reliability depend on the quality and availability of the relevant data and models.
Case Study on Electrochemical series
Sure, here’s an example case study on the electrochemical series:
Case Study: Understanding the Electrochemical Series
Background Information:
An electrochemical series is a list of elements arranged in order of their tendency to undergo oxidation or reduction reactions. The order is based on the standard electrode potential of each element, which is a measure of the voltage generated when the element is connected to a standard hydrogen electrode under standard conditions.
Case:
Samantha is a chemistry student who is studying the electrochemical series. She is curious about how the order of the elements is determined and how it can be used to predict the outcome of chemical reactions. To better understand the concept, she decides to conduct an experiment using copper and zinc electrodes.
Experiment:
Samantha sets up an electrochemical cell with a copper electrode and a zinc electrode. She connects the two electrodes with a salt bridge and measures the voltage generated by the cell. She then repeats the experiment with a copper electrode and a silver electrode. She records the voltage generated by each cell and uses the data to determine the order of the elements in the electrochemical series.
Results:
Samantha’s experiment yields the following results:
- Copper electrode and zinc electrode: Voltage = 1.10 V
- Copper electrode and silver electrode: Voltage = 0.80 V
Based on these results, Samantha concludes that zinc has a greater tendency to undergo oxidation than copper, while copper has a greater tendency to undergo reduction than silver. She arranges the elements in order of their standard electrode potential, with the most reactive element at the top and the least reactive element at the bottom:
- Lithium
- Potassium
- Calcium
- Sodium
- Magnesium
- Aluminium
- Zinc
- Iron
- Tin
- Lead
- Hydrogen
- Copper
- Silver
- Mercury
- Platinum
- Gold
Conclusion:
By conducting this experiment and analyzing the results, Samantha was able to gain a deeper understanding of the electrochemical series and how it can be used to predict the outcome of chemical reactions. She now understands that the order of the elements is based on their standard electrode potential and that elements at the top of the list have a greater tendency to undergo oxidation, while elements at the bottom of the list have a greater tendency to undergo reduction. This knowledge will help her in future experiments and in understanding the behavior of various chemicals in electrochemical reactions.
White paper on Electrochemical series
Sure, here’s a white paper on the electrochemical series:
Introduction:
Electrochemistry is the study of chemical reactions that involve the transfer of electrons. These reactions can be divided into two types: oxidation and reduction. Oxidation is the process of losing electrons, while reduction is the process of gaining electrons. The electrochemical series is a list of elements arranged in order of their tendency to undergo oxidation or reduction reactions. The order is based on the standard electrode potential of each element, which is a measure of the voltage generated when the element is connected to a standard hydrogen electrode under standard conditions.
Explanation:
The electrochemical series is an important tool for predicting the outcome of chemical reactions. Elements at the top of the series have a greater tendency to undergo oxidation, while elements at the bottom of the series have a greater tendency to undergo reduction. For example, if a metal at the top of the series is placed in a solution containing ions of a metal lower in the series, the higher metal will oxidize the lower metal, causing it to undergo reduction. This process is called a displacement reaction.
The standard electrode potential of an element is a measure of its relative reactivity. The standard electrode potential of hydrogen is defined as 0 volts. Elements with a positive standard electrode potential have a greater tendency to undergo reduction than hydrogen, while elements with a negative standard electrode potential have a greater tendency to undergo oxidation than hydrogen. The electrode potential of an element can be determined by measuring the voltage generated when the element is connected to a standard hydrogen electrode under standard conditions.
Applications:
The electrochemical series has many applications in chemistry and industry. It is used in the production of metals by electrolysis, which involves the use of an electric current to drive a chemical reaction. The electrochemical series is also used in batteries and fuel cells, which convert chemical energy into electrical energy. In addition, the electrochemical series is used in corrosion studies, where it is used to predict the rate and extent of corrosion of metals in different environments.
Conclusion:
The electrochemical series is an important tool for understanding chemical reactions that involve the transfer of electrons. It is based on the standard electrode potential of each element and provides a list of elements arranged in order of their tendency to undergo oxidation or reduction reactions. The electrochemical series has many applications in chemistry and industry, including the production of metals, batteries and fuel cells, and corrosion studies. Understanding the electrochemical series is essential for predicting the outcome of chemical reactions and designing new technologies based on electrochemistry.