MTE 271 EXAM 4 QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026
Which type of magnetism is described as: a metallic material containing permanent and aligned
magnetic moments that result from the incomplete cancellation of magnetic spin moments; these are
present even in the absence of an external field? - Answers Ferrimagnetism
A material shows weak attraction to a magnetic field due to unpaired electrons, but has no
magnetization when the field is removed. - Answers Paramagnetism
A material exhibits no net magnetic moment because adjacent atomic moments are equal in
magnitude and opposite in direction. - Answers Antiferromagnetism
A material exhibits strong permanent magnetization, with all atomic moments aligned in the same
direction. - Answers Ferromagnetism
A material is slightly repelled by a magnetic field and has no permanent magnetic moments. -
Answers Diamagnetism
-All magnetic moments align in same direction
-Strong permanent magnetization
- Exists without external field
examples are Fe, Ni, Co - Answers Ferromagnetism
-Magnetic moments are equal and opposite
-Perfect cancellation → net = 0
-No permanent magnetization - Answers Antiferromagnetism
-Moments are opposite BUT unequal
-Incomplete (partial) cancellation
-Net magnetization ≠ 0
-Exists without external field
-Usually found in ceramics (ferrites) - Answers Ferrimagnetism
-Has unpaired electrons
-Weak attraction to magnetic field
-Only magnetized when field is applied
-No permanent magnetization
-Magnetization disappears when field is removed - Answers Paramagnetism
-No unpaired electrons
-Weak repulsion from magnetic field
-Present in all materials, but usually very weak
-Caused by induced magnetic fields opposing applied field - Answers Diamagnetism
Which of the following characteristics is (are) displayed by hard magnetic materials?
(a) A relatively small hysteresis loop
(b) A relatively large hysteresis loop
(c) Magnetization and demagnetization may be achieved using relatively low applied fields
(d) Magnetization and demagnetization require relatively high applied fields
(e) Both A and C
(f) Both B and D - Answers (f) Both B and D
What type of magnet has:
-Large hysteresis loop
-High coercivity (hard to demagnetize)
-Hard to magnetize/demagnetize
-Retain magnetization - Answers Hard magnet
What type of magnet has:
-Small hysteresis loop
-Low coercivity
-Easy to magnetize/demagnetize
-Lose magnetization easily - Answers Soft magnet
What type of corrosion is:
-Loss of electrons
-Atom becomes more positive
-to become a cation
-occurs at anode - Answers Oxidation
What type of corrosion is:
, -Gain of electrons
-Atom becomes more negative
- becomes an anion
-occurs at cathode - Answers Reduction
What reaction occurs as the anode - Answers oxidation
what reaction occurs at the cathode - Answers reduction
Metals located near the top of the galvanic series are:
(a) Cathodic
(b) Anodic
(c) Unreactive
(d) Reactive - Answers Cathodic and Unreactive
What describes the top of the galvanic series - Answers Cathodic:
Noble
Unreactive
Protected
Do NOT corrode easily
Examples: gold, platinum
What describes the bottom of the galvanic series - Answers Anodic:
Reactive
Corrode easily
Lose electrons
👉 Examples: zinc, magnesium
Describe the reactiveness of platinum and gold, vs zinc and magnesium - Answers Platinum and gold:
unreactive/noble
Zinc and magnesium: reactive
To galvanically protect a material, you should use groups of metals/alloys above or below it on the
galvanic series? - Answers Below (more reactive than the material)
Reactive metals will have _______ electrode potential than unreactive metals - Answers lower
reactive materials have _____ corrosion resistance - Answers poor
Oxidation of an atom involves the:
(a) Loss of electrons
(b) Gain of electrons - Answers (a) Loss of electrons
Reduction takes place at the:
(a) Cathode
(b) Anode - Answers (a) Cathode
Which of the following are reduction reactions?
(a) H2 → 2H+ + 2e-
(b) Fe 2+ → Fe 3+ + e-
(c) Al 3+ + 3e- → Al
(d) 2H+ + 2e- → H2 + 2e- - Answers c and d
An overall electrochemical reaction must consist of at least:
(a) a single reduction reaction and a single oxidation reaction
(b) a single reduction reaction
(c) a single oxidation reaction
(d) multiple oxidation reactions
(e) multiple reduction reactions - Answers (a) a single reduction reaction and a single oxidation
reaction (REDOX)
Reactive materials have ______ electrode potential, unreactive materials have ______ electrode
potential - Answers low/negative, high/positive
what is the formation of a thin, protective oxide layer that prevents further corrosion - Answers
passivity
Why does aluminum resist corrosion? - Answers Forms a thin, protective oxide layer (passivation)
What materials form a passive layer? - Answers Aluminum
Stainless steel
Titanium
what are forms of Aqueous Corrosion - Answers 🔴 Uniform corrosion
Even material loss
Which type of magnetism is described as: a metallic material containing permanent and aligned
magnetic moments that result from the incomplete cancellation of magnetic spin moments; these are
present even in the absence of an external field? - Answers Ferrimagnetism
A material shows weak attraction to a magnetic field due to unpaired electrons, but has no
magnetization when the field is removed. - Answers Paramagnetism
A material exhibits no net magnetic moment because adjacent atomic moments are equal in
magnitude and opposite in direction. - Answers Antiferromagnetism
A material exhibits strong permanent magnetization, with all atomic moments aligned in the same
direction. - Answers Ferromagnetism
A material is slightly repelled by a magnetic field and has no permanent magnetic moments. -
Answers Diamagnetism
-All magnetic moments align in same direction
-Strong permanent magnetization
- Exists without external field
examples are Fe, Ni, Co - Answers Ferromagnetism
-Magnetic moments are equal and opposite
-Perfect cancellation → net = 0
-No permanent magnetization - Answers Antiferromagnetism
-Moments are opposite BUT unequal
-Incomplete (partial) cancellation
-Net magnetization ≠ 0
-Exists without external field
-Usually found in ceramics (ferrites) - Answers Ferrimagnetism
-Has unpaired electrons
-Weak attraction to magnetic field
-Only magnetized when field is applied
-No permanent magnetization
-Magnetization disappears when field is removed - Answers Paramagnetism
-No unpaired electrons
-Weak repulsion from magnetic field
-Present in all materials, but usually very weak
-Caused by induced magnetic fields opposing applied field - Answers Diamagnetism
Which of the following characteristics is (are) displayed by hard magnetic materials?
(a) A relatively small hysteresis loop
(b) A relatively large hysteresis loop
(c) Magnetization and demagnetization may be achieved using relatively low applied fields
(d) Magnetization and demagnetization require relatively high applied fields
(e) Both A and C
(f) Both B and D - Answers (f) Both B and D
What type of magnet has:
-Large hysteresis loop
-High coercivity (hard to demagnetize)
-Hard to magnetize/demagnetize
-Retain magnetization - Answers Hard magnet
What type of magnet has:
-Small hysteresis loop
-Low coercivity
-Easy to magnetize/demagnetize
-Lose magnetization easily - Answers Soft magnet
What type of corrosion is:
-Loss of electrons
-Atom becomes more positive
-to become a cation
-occurs at anode - Answers Oxidation
What type of corrosion is:
, -Gain of electrons
-Atom becomes more negative
- becomes an anion
-occurs at cathode - Answers Reduction
What reaction occurs as the anode - Answers oxidation
what reaction occurs at the cathode - Answers reduction
Metals located near the top of the galvanic series are:
(a) Cathodic
(b) Anodic
(c) Unreactive
(d) Reactive - Answers Cathodic and Unreactive
What describes the top of the galvanic series - Answers Cathodic:
Noble
Unreactive
Protected
Do NOT corrode easily
Examples: gold, platinum
What describes the bottom of the galvanic series - Answers Anodic:
Reactive
Corrode easily
Lose electrons
👉 Examples: zinc, magnesium
Describe the reactiveness of platinum and gold, vs zinc and magnesium - Answers Platinum and gold:
unreactive/noble
Zinc and magnesium: reactive
To galvanically protect a material, you should use groups of metals/alloys above or below it on the
galvanic series? - Answers Below (more reactive than the material)
Reactive metals will have _______ electrode potential than unreactive metals - Answers lower
reactive materials have _____ corrosion resistance - Answers poor
Oxidation of an atom involves the:
(a) Loss of electrons
(b) Gain of electrons - Answers (a) Loss of electrons
Reduction takes place at the:
(a) Cathode
(b) Anode - Answers (a) Cathode
Which of the following are reduction reactions?
(a) H2 → 2H+ + 2e-
(b) Fe 2+ → Fe 3+ + e-
(c) Al 3+ + 3e- → Al
(d) 2H+ + 2e- → H2 + 2e- - Answers c and d
An overall electrochemical reaction must consist of at least:
(a) a single reduction reaction and a single oxidation reaction
(b) a single reduction reaction
(c) a single oxidation reaction
(d) multiple oxidation reactions
(e) multiple reduction reactions - Answers (a) a single reduction reaction and a single oxidation
reaction (REDOX)
Reactive materials have ______ electrode potential, unreactive materials have ______ electrode
potential - Answers low/negative, high/positive
what is the formation of a thin, protective oxide layer that prevents further corrosion - Answers
passivity
Why does aluminum resist corrosion? - Answers Forms a thin, protective oxide layer (passivation)
What materials form a passive layer? - Answers Aluminum
Stainless steel
Titanium
what are forms of Aqueous Corrosion - Answers 🔴 Uniform corrosion
Even material loss
