Corrosion in Chemical Industry: Electrochemistry

Play an AI-generated podcast conversation about this lesson

What is the main type of process involved in the corrosion of metallic materials?

Optical

Mechanical

Electrochemical (correct)

Thermal

In a galvanic cell, what occurs at the anode?

Reduction

Oxidation (correct)

Hydration

Evaporation

What are the two components required to form a galvanic cell?

Electrical insulators

Metallic alloys

Chemical precipitates

Electrodes and an electrolyte (correct)

How is electrochemical corrosion of metals defined?

Damaging of metal in aqueous medium Signup and view all the answers

In an electrochemical system, what must occur between the anode and cathode?

Electron transfer Signup and view all the answers

What chemical process takes place at the cathode in a galvanic cell?

Reduction Signup and view all the answers

What is a half-cell with a pure metal electrode immersed in a 1M solution of its ions at 25°C called?

Reference electrode Signup and view all the answers

In the Nernst equation, what does 'n' represent?

Moles of electrons Signup and view all the answers

What does the negative value of Gibbs free energy (ΔG) indicate?

Spontaneous reaction Signup and view all the answers

What does the standard-state free energy refer to in electrochemical effects?

Ideal conditions for reactants and products Signup and view all the answers

Which electrode is commonly used as a reference electrode in electrochemical studies?

Hydrogen electrode Signup and view all the answers

What does the Nernst equation express in relation to a cell?

Electromotive force in terms of reactants, products, and temperature Signup and view all the answers

What is the term used to describe the electric potential between two cell halves?

Electrode potential Signup and view all the answers

At what temperature was the potential of 0.780 V measured for a copper–iron galvanic cell?

25°C Signup and view all the answers

What does the magnitude of a voltage represent in electrochemical oxidation–reduction reactions?

The driving force for the reaction Signup and view all the answers

Which term is used to rate metallic materials based on their tendency to experience oxidation when coupled to other metals in solutions of their respective ions?

Electrode potential Signup and view all the answers

Which instrument can be used to determine the magnitude of the electric potential between two cell halves?

Voltmeter Signup and view all the answers

What is the driving force for electrochemical oxidation–reduction reactions?

The magnitude of such a voltage Signup and view all the answers

Which equation represents the reduction reaction in the electrochemical corrosion of metals?

2H+ + 2e- → H2° Signup and view all the answers

What is the name of the reaction in which zinc valence increases from 0 to +2, liberating electrons?

An oxidation Signup and view all the answers

What is the role of the electrolytic conductor in an electrochemical cell?

It provides the movement of current Signup and view all the answers

Which component in an electrochemical cell is the site of oxidation?

Anode Signup and view all the answers

What is the term used to describe the corrosion that involves the movement of ions in the electrolytic conductor?

Electrochemical corrosion Signup and view all the answers

Which reaction represents the oxidation of zinc in the electrochemical corrosion of metals?

Zn° → Zn+2 + 2e- Signup and view all the answers

What happens to the corrosion rate of steel when fine precipitated n-carbide and cementite occur?

The corrosion rate is accelerated Signup and view all the answers

At what temperature does cementite merge with other particles, leading to a reduction in corrosion rate?

At tempering temperatures over 500°C Signup and view all the answers

What is the anode reaction in a Salt Concentration Cell?

Cu° → Cu+2 + 2e- Signup and view all the answers

What is the cathode reaction in a Differential Aeration Cell?

O2 + H2O + 2e-→ 2OH- Signup and view all the answers

What causes the pipe in sandy soil to corrode more?

Differential aeration cells Signup and view all the answers

Where are Differential Temperature Cells typically found?

In heat exchangers, boilers, immersion heaters, and similar equipment Signup and view all the answers