Chemistry, HSSC-KPK Second Year. This chapter is split into 24 topics and has
581 practice questions. The topics covered are listed below, followed by
10 free sample questions from the chapter.
Topics in this chapter
Hair dyes and adhesives30 questions
Synthetic polymers: addition versus condensation, and PVC26 questions
Fractional distillation of petroleum26 questions
Petrochemicals: definition, history, and raw materials27 questions
Nylon preparation and uses of PVC and Nylon25 questions
Cosmetics: lipstick, nail varnish, and nail polish remover26 questions
Industrial chemistry: introduction, economy of Pakistan, and safety considerations26 questions
Dyes: chemical composition, chromophore, and auxochrome26 questions
Pesticides: DDT, biomagnification, and parathion25 questions
Classification of dyes into ten application-based types28 questions
Industrial chemistry - products, trade figures and arithmetic24 questions
Dyes - Table 22.1 row by row and chromophore comparisons21 questions
Dye classes - examples, fibres and dyeing conditions22 questions
Pesticides - poisons, DDT persistence and parathion arithmetic23 questions
Petrochemicals from methane - Table 22.3 cell by cell23 questions
Petrochemicals from ethylene - Table 22.4 and the history of petrochemicals22 questions
Addition polymers - polyethylene and degree of polymerisation arithmetic21 questions
PVC - vinyl chloride route, suspension recipe and arithmetic20 questions
Condensation polymers and nylon - structures and rope-trick calculations20 questions
Industrial chemistry exercise, key points and synthetic fibre items23 questions
Lipstick and nail varnish - ingredients, colours and formulation details25 questions
Nail polish remover and hair dyes - composition, action and hazards24 questions
Adhesives - importance, drying, pressure, contact, hot and reactive types25 questions
Sample questions: Industrial Chemistry
10 sample questions with the correct answer and an explanation. Try to answer each one before reading the explanation.
Q1. According to the chapter, to secure processes from excessive competition and ensure an adequate return on large sums spent, what must companies focus on?
A. Cutting all research spending immediately
B. Research and continuing progress to replace obsolescent processes and equipment(correct answer)
C. Reducing the workforce to zero
D. Ignoring competitors entirely
Answer: B.To secure the processes from excessive competition and to ensure an adequate return for large sums spent on research and plant, and to guarantee progress to continue profits and replace obsolescent processes and equipment, much attention and money must be spent upon continuing research and development.
Q2. Which correctly summarizes why chemical processing involves both chemical conversions and physical operations?
A. Chemical conversions transform raw materials into higher-value products, while physical operations like heat transfer and temperature control are necessary to secure good yield and purity during that conversion(correct answer)
B. Chemical processing involves only physical operations, with no chemical conversions
C. Chemical processing involves only chemical reactions, with no physical operations ever required
D. Physical operations and chemical conversions are entirely unrelated to industrial yield
Answer: A.Chemical processing involves chemical conversion (e.g., sulphuric acid manufacture, nylon production) as well as physical operations such as heat transfer and temperature control, which are intimately necessary to secure the good yield required by competitive industry.
Q3. Which correctly explains the full mechanism by which DDT's chemical stability leads to harm at the top of a food chain, even when applied in small quantities?
A. DDT is chemically stable (10-15 year half-life) and non-polar (dissolving preferentially in fat, not water); this allows it to accumulate unchanged in the fatty tissue of organisms at each step of the food chain, becoming progressively more concentrated (biomagnified) as it moves from insects to fish to birds and humans(correct answer)
B. DDT breaks down within hours, so it cannot accumulate in any organism
C. DDT is highly water-soluble, so it stays diluted evenly throughout an ecosystem with no concentration effect
D. DDT's biomagnification has nothing to do with its chemical stability or polarity
Answer: A.DDT's long half-life (chemical stability) and non-polar, water-insoluble, fat-soluble nature together allow it to persist unchanged and accumulate in fatty tissue at each trophic level, so that concentrations increase dramatically (biomagnification) as it passes up the food chain from insects to fish to fish-eating birds and even humans, even when applied at very low initial concentrations.
Q4. The most basic raw materials supplied by petroleum refineries or natural gas companies include LPG, natural gas from cracking operations, liquid distillate, and:
A. Selected or isomerized cyclic fractions for aromatics(correct answer)
B. Only distilled water
C. Only pure elemental carbon
D. Only table salt
Answer: A.The most basic raw materials supplied by petroleum refineries or natural gas companies are LPG, natural gas from cracking operations, liquid distillate (C4 to C6), distillate from special cracking processes, and selected or isomerized cyclic fractions for aromatics.
Q5. Which correctly ranks the seven main fractions of petroleum from lowest to highest boiling range/temperature of collection?
A. Gasoline < refinery gas < kerosine < petroleum ether < heavy oil < light naphtha < lubricating oil
B. Refinery gas < petroleum ether < light naphtha < gasoline < kerosine < heavy oil < lubricating oil(correct answer)
C. All seven fractions are collected at exactly the same temperature
D. Lubricating oil < heavy oil < kerosine < gasoline < light naphtha < petroleum ether < refinery gas
Answer: B.In fractional distillation, the fractions are collected in order of increasing boiling range: refinery gas (below 20°C) < petroleum ether (20-60°C) < light naphtha (60-100°C) < gasoline (80-180°C) < kerosine (160-300°C) < heavy oil (300-400°C) < lubricating oil (above 400°C).
Q6. Which correctly describes the overall relationship between hydrocarbon chain length and the practical use of a petroleum fraction, based on the seven fractions discussed?
A. Shorter carbon chains always produce solid residues like asphalt
B. Carbon chain length has no relationship to a fraction's boiling point or use
C. Longer carbon chains always produce gaseous fuels like refinery gas
D. As carbon chain length increases across the fractions (from C1-C4 gases to C30+ solids), the fractions transition from gaseous fuels, through liquid motor/heating fuels, to viscous lubricants and finally solid road-paving material(correct answer)
Answer: D.As you move through the fractions from refinery gas (C1-C4, gas) to gasoline (C7-C10, liquid fuel) to lubricating oil (C18-C20, viscous liquid) to the final residue asphalt (C30+, solid), increasing carbon chain length correlates with increasing boiling point and a shift from gas to liquid fuel to viscous lubricant to solid paving material.
Q7. Which correctly captures the fundamental chemical difference between addition polymerization and condensation polymerization?
A. Both processes are chemically identical with no meaningful distinction
B. Addition polymerization always releases water, while condensation polymerization never releases any byproduct
C. Condensation polymerization only occurs with inorganic monomers
D. Addition polymerization simply joins monomers with no byproduct, keeping the same empirical formula as the monomer; condensation polymerization joins monomers while releasing a small molecule such as water at each linkage(correct answer)
Answer: D.Addition polymers form by the monomer simply adding to itself repeatedly (empirical formula unchanged, no byproduct), while condensation polymers form when a bifunctional monomer reacts with another, releasing a small molecule (water, HCl, NH3, or methanol) at each step.
Q8. Which correctly describes why different synthetic fibers (nylon, Kevlar, polyester) are chosen for different applications, based on the applied reading?
A. Each fiber has distinct properties (nylon's strength for gears/carpets, Kevlar's toughness for bullet-proof vests, polyester's hydrophobicity for garments/sails) that suit it to specific uses(correct answer)
B. The choice of fiber has nothing to do with its physical properties
C. Only nylon has any practical use; Kevlar and polyester are purely decorative
D. All three synthetic fibers have identical properties and are used interchangeably
Answer: A.The applied reading shows that each synthetic fiber's specific properties determine its application: nylon's mechanical strength suits gears, bearings, and carpets; Kevlar's toughness suits bullet-proof vests and tyres; and polyester's hydrophobic property suits garments, jackets, and sails.
Q9. Which correctly distinguishes nylon (6,6) from nylon (6,10) in terms of their monomer composition?
A. Both nylon (6,6) and nylon (6,10) use identical monomers
B. Nylon (6,6) uses vinyl chloride; nylon (6,10) uses ethylene
C. Neither nylon type has a defined monomer composition
D. Nylon (6,6) uses hexamethylene diamine and adipic acid (both 6-carbon); nylon (6,10) uses hexamethylene diamine (6-carbon) and sebacoyl chloride/decanedioyl dichloride (10-carbon)(correct answer)
Answer: D.Nylon (6,6) is made from hexamethylene diamine and adipic acid (hexanedioic acid), both 6-carbon compounds, while nylon (6,10), prepared in the nylon rope trick, uses hexamethylene diamine (6-carbon) and decanedioyl dichloride/sebacoyl chloride (10-carbon), giving the different numbering.
Q10. Which correctly summarizes the key distinguishing principle between non-reactive and reactive adhesives?
A. Both types of adhesives harden by exactly the same physical process
B. Reactive adhesives require no external energy or chemical component of any kind
C. Non-reactive adhesives harden by physical processes like solvent evaporation or cooling, while reactive adhesives harden through a genuine chemical reaction with the material or between adhesive components(correct answer)
D. Non-reactive adhesives always chemically react with the bonded material; reactive adhesives never do
Answer: C.Non-reactive adhesives (drying, pressure-sensitive, contact, hot) cure by physical means such as solvent evaporation or cooling from a molten state, while reactive adhesives (multipart or one-part) harden via genuine chemical reactions, either between mixed components or with an external energy source like heat, moisture, or light.