Ethics and Values in Chemistry: Unit 1 MCQs Solved | Federal Board FSc Part 2 New Book

Question i:

Statement:
What is cognitive bias?

Options:
a) The process of making decisions based on logical reasoning.
b) The tendency to make decisions based on personal characteristics and beliefs.
c) The evaluation of arguments using empirical evidence.
d) The method of constructing arguments using logical fallacies.

Correct Answer:
b

Explanation:
Cognitive bias refers to systematic errors in thinking that arise from personal beliefs, experiences, or emotions, leading to irrational judgments. Option b is correct because cognitive biases stem from subjective influences (e.g., stereotypes, emotions) rather than objective analysis.

  • a is incorrect: Logical reasoning opposes cognitive bias, which is inherently illogical.
  • c is incorrect: Cognitive biases often ignore empirical evidence in favor of preconceived notions.
  • d is incorrect: Logical fallacies are flawed argument structures, while cognitive biases are unconscious mental shortcuts.

Tips and Tricks:

  • Key phrase: “tendency” – Cognitive biases are unconscious tendencies, not deliberate methods.
  • Remember: If an option describes objectivity (e.g., “logical reasoning,” “empirical evidence”), it likely contradicts cognitive bias.

Question ii:

Statement:
What is a hasty generalization fallacy?

Options:
a) Drawing a conclusion based on a large, representative sample.
b) Drawing a conclusion based on insufficient evidence.
c) Drawing a conclusion by misrepresenting an opponent’s argument.
d) Drawing a conclusion based on a false cause-and-effect relationship.

Correct Answer:
b

Explanation:
Hasty generalization occurs when a broad conclusion is made from inadequate or unrepresentative data. Option b directly defines this fallacy (e.g., “All crows are black” after seeing two crows).

  • a is incorrect: Large samples support reliable generalizations, making this the opposite of hasty generalization.
  • c describes the straw man fallacy.
  • d describes the post hoc fallacy.

Tips and Tricks:

  • Spot keywords: “insufficient evidence,” “small sample size,” or “jumping to conclusions.”
  • Avoid confusion: If an option mentions “large sample” (a) or “cause-and-effect” (d), it refers to other fallacies.

Question iii:

Statement:
What does the post hoc ergo propter hoc fallacy assume?

Options:
a) One event is caused by another simply because it follows it.
b) One event is unrelated to another.
c) One event is the result of a thorough investigation.
d) One event is part of a larger series of events.

Correct Answer:
a

Explanation:
The post hoc fallacy (Latin: “after this, therefore because of this”) assumes Event A causes Event B solely because B occurs after A (e.g., “I wore a red shirt, then my team won; therefore, my shirt caused the win”).

  • b is incorrect: The fallacy assumes a false connection, not unrelatedness.
  • c is incorrect: This describes evidence-based reasoning, not a fallacy.
  • d is incorrect: While events may be part of a series, post hoc specifically confuses sequence with causation.

Tips and Tricks:

  • Translate the Latin: Post hoc = “after this.” If the answer highlights temporal sequence as causation, it’s correct.
  • Real-world example: Superstitions (e.g., “I broke a mirror, then got into an accident; the mirror caused the accident”).

Question iv:

Statement:
Which fallacy involves attacking a distorted version of an opponent’s claim?

Options:
a) Confirmation Bias
b) Hasty Generalizations
c) The Straw Man Fallacy
d) Redefinition

Correct Answer:
c

Explanation:
The straw man fallacy misrepresents an opponent’s argument to make it easier to attack (e.g., oversimplifying “Reduce carbon emissions” to “You want to destroy the economy!”).

  • a is incorrect: Confirmation bias is seeking evidence to support preexisting beliefs, not misrepresenting arguments.
  • b is incorrect: Hasty generalization involves flawed sampling, not distortion of claims.
  • d is incorrect: Redefinition changes word meanings but isn’t a formal fallacy.

Tips and Tricks:

  • Visualize the name: A “straw man” is a weak dummy substitute for the real argument.
  • Identify distortion: If an option describes twisting or exaggerating an opponent’s view, it’s likely straw man.

Summary of Correct Answers:

QuestionCorrect Answer
ib
iib
iiia
ivc

Key Study Tip: Memorize fallacies using real-life examples. For instance:

  • Cognitive bias → Believing a news article aligns with your views without fact-checking (confirmation bias).
  • Hasty generalization → “My neighbor’s dog bit me; all dogs are aggressive!”
  • Post hoc → “It rained after I washed my car; my car wash caused the rain.”
  • Straw man → “You support renewable energy? So you’d leave us all in the dark!”

Question iv:

Statement:
Which fallacy involves attacking a distorted version of an opponent’s claim?

Options:
a) Confirmation Bias
b) Hasty Generalizations
c) The Straw Man Fallacy
d) Redefinition

Correct Answer:
c) The Straw Man Fallacy

Explanation:
The Straw Man Fallacy occurs when someone misrepresents or oversimplifies an opponent’s argument to make it easier to attack. For example:

  • Original argument: “We should reduce fossil fuel use.”
  • Straw man distortion: “You want to ban all cars and destroy the economy!”
    Why others are incorrect:
  • a) Confirmation bias involves favoring information that confirms preexisting beliefs.
  • b) Hasty generalizations draw conclusions from insufficient evidence.
  • d) Redefinition changes word meanings but isn’t a formal fallacy.

Tips and Tricks:

  • Visualize a “straw man” dummy: Attacking a weak, fake version of the real argument.
  • Key phrase: “distorted version” = immediate link to Straw Man.

Question v:

Statement:
What does the principle of Occam’s Razor advocate?

Options:
a) Choosing the most complex explanation for an event
b) Choosing the simplest explanation for an event
c) Choosing an explanation based on tradition
d) Choosing an explanation based on authority

Correct Answer:
b) Choosing the simplest explanation for an event

Explanation:
Occam’s Razor states that when multiple explanations exist, the one with the fewest assumptions is most likely correct. Simplicity minimizes unnecessary complexity.
Why others are incorrect:

  • a) Complexity often introduces unwarranted assumptions.
  • c) Tradition may perpetuate errors (e.g., appeal to tradition fallacy).
  • d) Authority doesn’t guarantee truth (e.g., appeal to authority fallacy).

Tips and Tricks:

  • Remember: “The simplest solution is usually the best.”
  • Example: Preferring gravity over invisible angels to explain falling objects.

Question vi:

Statement:
What is an example of the appeal to tradition fallacy?

Options:
a) Believing a theory is valid because an expert supports it
b) Believing a practice is correct because it has always been done that way
c) Believing an argument because it cannot be tested
d) Believing a hypothesis because it is the simplest explanation

Correct Answer:
b) Believing a practice is correct because it has always been done that way

Explanation:
Appeal to tradition assumes longevity implies validity (e.g., “Bloodletting works because doctors did it for centuries”).
Why others are incorrect:

  • a) Describes appeal to authority.
  • c) Relates to untestable claims, not tradition.
  • d) Describes Occam’s Razor.

Tips and Tricks:

  • Spot phrases like “we’ve always done this” or “it’s traditional.”
  • Tradition ≠ correctness (e.g., historical use of lead in makeup).

Question vii:

Statement:
Which of the following is a pro of chemical substances?

Options:
a) They always have a negative impact on health
b) They reduce carbon footprints through clean energy technologies
c) They are always safe for workers
d) They never cause environmental pollution

Correct Answer:
b) They reduce carbon footprints through clean energy technologies

Explanation:
Chemicals enable green technologies (e.g., lithium-ion batteries for electric cars, catalytic converters).
Why others are incorrect:

  • a) and d) use absolutes (“always,” “never”) – chemicals have nuanced impacts.
  • c) Safety depends on handling/regulations, not inherent properties.

Tips and Tricks:

  • Reject absolute terms; focus on context-specific benefits.
  • Link “clean energy” to chemical innovation (solar panels, biofuels).

Question viii:

Statement:
What is a con of weak or outdated regulations regarding chemicals?

Options:
a) They protect public health effectively
b) They foster innovation in chemical processes
c) They fail to address current risks
d) They reduce compliance costs for companies

Correct Answer:
c) They fail to address current risks

Explanation:
Outdated regulations ignore modern threats (e.g., nanoplastics, PFAS “forever chemicals”) due to evolving science.
Why others are incorrect:

  • a) Weak regulations endanger health.
  • b) Innovation requires safety frameworks to avoid disasters (e.g., Bhopal gas tragedy).
  • d) Reduced costs for companies ≠ public benefit.

Tips and Tricks:

  • “Fail to address” signals unmanaged dangers.
  • Historical cases: Asbestos regulations lagged decades behind evidence.

Question ix:

Statement:
What role do premises play in a scientific argument?

Options:
a) They oppose the main claim
b) They provide the foundation for the claim
c) They represent the conclusion
d) They are unsupported assumptions

Correct Answer:
b) They provide the foundation for the claim

Explanation:
Premises are evidence-based statements supporting a conclusion (e.g., “CO₂ traps heat [premise 1]; human activity emits CO₂ [premise 2] → thus, humans cause warming [claim]”).
Why others are incorrect:

  • a) Counterclaims oppose; premises support.
  • c) Conclusions follow from premises.
  • d) Premises should be empirically validated.

Tips and Tricks:

  • Premises = “building blocks” of arguments.
  • Test: “Does this statement back up the main idea?”

Question x:

Statement:
In the context of written articles, what would be a counterclaim for promoting electric vehicles?

Options:
a) Electric cars produce no emissions
b) Urban areas suffer from high air pollution
c) Electric cars still have high environmental costs due to battery production

Correct Answer:
c) Electric cars still have high environmental costs due to battery production

Explanation:
A counterclaim challenges the main argument. Promoting EVs often highlights zero tailpipe emissions (a), but battery production involves mining, energy use, and waste (c).
Why others are incorrect:

  • a) Supports EV promotion.
  • b) Justifies EVs as a solution to pollution.

Tips and Tricks:

  • Counterclaims introduce drawbacks/limitations.
  • Key conflict: “Environmental costs” vs. perceived sustainability.

Answer Summary:

QCorrectKey Concept
ivcStraw Man Fallacy
vbOccam’s Razor
vibAppeal to Tradition
viibPros of Chemicals
viiicRegulation Cons
ixbPremises in Arguments
xcCounterclaims

Transition Elements Solved Exercise PTB

Transition Elements Exercsie

Explore the solved exercise of Transition Elements from Punjab Textbook Board (PTB). Get detailed solutions, explanations, and notes tailored for college students to master key concepts of chemistry effectively.

Enhance your understanding of Transition Elements with this comprehensive solved exercise guide tailored for Punjab Textbook Board (PTB) students. Covering essential topics like electronic configurations, oxidation states, complex compounds, catalytic properties, and magnetic behavior, this guide provides step-by-step solutions to textbook exercises. Perfect for exam preparation, it includes solved MCQs, short questions, long questions, and conceptual problems. Aligned with the PTB syllabus, this resource simplifies the study of transition metals for easy learning and academic success.

(a) Binding energy
The binding energy of transition elements is influenced by the number of unpaired electrons in the d-orbitals. More unpaired electrons lead to stronger metallic bonds, increasing the binding energy.

Q.4 How does the electronic configuration of the valence shell affect the following properties of the transition elements?

(b) Paramagnetism
Paramagnetism in transition metals arises due to the presence of unpaired d-electrons. The more unpaired electrons there are, the stronger the paramagnetic property of the element.

(c) Melting points
The melting points of transition metals generally increase with the number of unpaired d-electrons, as this leads to stronger metallic bonding. However, this trend can vary across the series.

(d) Oxidation states
Transition elements exhibit variable oxidation states due to the similar energy levels of their 3d and 4s electrons. As the number of valence electrons available for bonding increases, the number of possible oxidation states also increases.

Q.5 Explain the following terms giving examples.

(a) Ligands
Ligands are ions or molecules that can donate a pair of electrons to the central metal atom/ion to form a coordination bond. Example: In [Cu(NH₃)₄]²⁺, ammonia (NH₃) acts as a ligand.

(b) Coordination sphere
The coordination sphere consists of the central metal atom/ion and the ligands directly attached to it. For example, in [Fe(CN)₆]⁴⁻, the coordination sphere is Fe and six cyanide ions (CN⁻).

(c) Substitutional alloy
A substitutional alloy forms when atoms of one element replace atoms of another element in a metal’s crystal lattice. Example: Brass is a substitutional alloy of copper and zinc.

(d) Central metal atom
The central metal atom is the atom in a coordination complex to which ligands are bonded. For example, in [Co(NH₃)₆]³⁺, cobalt (Co) is the central metal atom.

Q.6 Describe the rules for naming coordination complexes and give examples.

Answer:

  1. Cation before anion: The name of the cationic part comes before the anionic part.
  2. Ligands named first: Ligands are named before the central metal atom. Neutral ligands use their molecule name, while anionic ligands use the suffix ‘-o’.
  • Example: H₂O becomes aqua, NH₃ becomes ammine, Cl⁻ becomes chloro.
  1. Number of ligands: Prefixes like mono-, di-, tri-, etc., indicate the number of each type of ligand.
  2. Metal name: The metal is named, followed by its oxidation state in Roman numerals.
  • Example: [Cr(H₂O)₆]³⁺ is named as hexaaquachromium(III) ion.
  1. For anionic complexes: The metal’s name ends with the suffix ‘-ate’.
  • Example: [Co(CN)₆]³⁻ is named as hexacyanocobaltate(III).

Q.7 What is the difference between wrought iron and steel? Explain the Bessemer’s process for the manufacture of steel.

Answer:

  • Wrought iron is a nearly pure form of iron with less than 0.08% carbon content, making it soft and malleable. It is used for decorative ironwork.
  • Steel contains more carbon (0.1% to 2%), making it stronger and harder than wrought iron. It is widely used in construction and manufacturing.

Bessemer’s process:
The Bessemer process is a method for making steel by blowing air through molten pig iron to oxidize and remove impurities like carbon, silicon, and manganese. The process helps in producing steel rapidly and at a lower cost.

Q.8 Explain the following giving reasons.

(a) Why does damaged tin-plated iron get rusted quickly?
Answer: When tin-plated iron is damaged, the exposed iron reacts with water and oxygen, forming rust. Since tin is less reactive than iron, the iron oxidizes (rusts) faster when exposed in the presence of tin, acting as a sacrificial element.

(b) Under what conditions does aluminum corrode?
Answer: Aluminum corrodes when exposed to moist environments containing salts or acids. However, aluminum forms a protective layer of aluminum oxide (Al₂O₃) that prevents further corrosion under normal conditions.

(c) How does the process of galvanizing protect iron from rusting?
Answer: Galvanizing involves coating iron with a layer of zinc. Zinc acts as a sacrificial anode, meaning it corrodes in place of the iron. Even if the zinc coating is damaged, the exposed iron remains protected as the zinc continues to corrode preferentially.

Q.9 How chromate ions are converted into dichromate ions?

Answer:
Chromate ions CrO42- are converted into dichromate ions Cr2O7^2- in acidic conditions by the following equilibrium reaction:

2 CrO4^2- + 2 H^+ → Cr2O72- + H2O

This conversion involves the protonation of chromate ions, leading to the formation of dichromate ions.

Q.10 Describe the preparation of KMnO₄ and K₂CrO₄.

Answer:

Preparation of Potassium Permanganate (KMnO₄):

  1. Oxidation of Manganese Dioxide (MnO₂): Manganese dioxide is fused with potassium hydroxide (KOH) in the presence of an oxidizing agent like potassium nitrate (KNO₃):
    2 MnO2 + 4 KOH + O2 → 2 K2MnO4 + 2 H2O
  2. Conversion of Potassium Manganate to Potassium Permanganate: Potassium manganate ((K_2MnO_4)) is oxidized in an acidic or neutral medium to form potassium permanganate:
    3 K2MnO4 + 2 H2O → 2 KMnO4 + MnO2 + 4 KOH

Preparation of Potassium Chromate (K₂CrO₄):

  1. Oxidation of Chromite Ore (FeCr₂O₄): Chromite ore is heated with sodium carbonate (Na₂CO₃) in the presence of air or oxygen, yielding sodium chromate ((Na₂CrO₄)):
    4 FeCr2O4 + 8 Na2CO3 + 7 O2 → 8 Na2CrO4 + 2 Fe2O3 + 8 CO2
  2. Conversion to Potassium Chromate: Sodium chromate is treated with potassium chloride (KCl), forming potassium chromate:
    Na2CrO4 + 2 KCl → K2CrO4 + 2 NaCl

Q.11 Give systematic names to the following complexes:

(a) [Fe(CO)₅]
Answer: Pentacarbonyliron(0)

(b) [Co(NH₃)₆]Cl₃
Answer: Hexaamminecobalt(III) chloride

(c) [Fe(H₂O)₆]²⁺
Answer: Hexaaquairon(II) ion

(d) Na₃[CoF₆]
Answer: Sodium hexafluorocobaltate(III)

(e) K₃[Cu(CN)₄]
Answer: Potassium tetracyanocuprate(I)

(f) K₂[PtCl₆]
Answer: Potassium hexachloroplatinate(IV)

(g) [Pt(OH)₂(NH₃)₄]SO₄
Answer: Tetraamminehydroxoplatinum(IV) sulfate

(h) [Cr(OH)₃(H₂O)₃]
Answer: Trihydroxotriaquachromium(III)