Astringents: Potash alum MCQs With Answer

Astringents: Potash alum MCQs With Answer

Potash alum (KAl(SO4)2·12H2O) is a classic astringent used in topical formulations and hemostatic applications. This concise, SEO-friendly introduction explores potash alum’s chemistry, mechanism of action (protein precipitation and mild vasoconstriction), pharmaceutical uses, identification tests, formulation considerations, stability, safety, and comparative astringents relevant to B. Pharm students. Understanding potash alum’s physicochemical properties, assay methods, and clinical implications is essential for formulation and quality control in pharmacy practice. These MCQs emphasize both theory and practical aspects to prepare you for exams and lab work. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What is the chemical formula of potash alum?

• KAl(SO4)2·12H2O
• K2SO4
• Al2(SO4)3
• KCl

Correct Answer: KAl(SO4)2·12H2O

Q2. Potash alum belongs to which class of compounds used as astringents?

• Sulfate salts of a metal and aluminum
• Organic tannins
• Zinc oxide derivatives
• Chloride salts

Correct Answer: Sulfate salts of a metal and aluminum

Q3. The primary mechanism by which potash alum exerts astringent action is:

• Protein precipitation and mucosal contraction
• Enzymatic inhibition of proteases
• Systemic vasodilation
• Blocking bacterial cell wall synthesis

Correct Answer: Protein precipitation and mucosal contraction

Q4. Which ion in potash alum primarily gives a characteristic lilac flame test?

• Potassium
• Aluminum
• Sulfate
• Hydrogen

Correct Answer: Potassium

Q5. Which reagent gives a white precipitate confirming the presence of sulfate ions in a potash alum solution?

• Barium chloride
• Sodium hydroxide
• Silver nitrate
• Ammonium molybdate

Correct Answer: Barium chloride

Q6. Which test reagent produces a red complex with aluminum ions, useful for identification of potash alum?

• Aluminon
• Phenolphthalein
• Potassium permanganate
• Ferric chloride

Correct Answer: Aluminon

Q7. Potash alum is most commonly used in pharmacy as a(n):

• Topical astringent and styptic agent
• Systemic antihypertensive
• Oral analgesic
• Local anesthetic

Correct Answer: Topical astringent and styptic agent

Q8. The hydration number in potash alum’s crystalline structure is:

• 12 molecules of water
• 6 molecules of water
• 4 molecules of water
• 0 molecules of water

Correct Answer: 12 molecules of water

Q9. Which property of potash alum makes it useful in controlling minor bleeding from capillaries?

• Protein coagulation causing vessel constriction
• Anticoagulant activity
• Systemic vasodilation
• Enzymatic fibrinolysis

Correct Answer: Protein coagulation causing vessel constriction

Q10. In formulation, potash alum is most compatible with which type of dosage forms?

• Topical solutions, lotions, and styptic pencils
• Intravenous injections
• Enteric-coated tablets for systemic delivery
• Oral sustained-release capsules

Correct Answer: Topical solutions, lotions, and styptic pencils

Q11. Which of the following best describes the solubility behavior of potash alum?

• Soluble in water, more soluble in hot water
• Insoluble in water
• Soluble only in organic solvents
• Soluble in oil

Correct Answer: Soluble in water, more soluble in hot water

Q12. A common pharmaceutical method to confirm aluminum in potash alum is precipitation as:

• Aluminum hydroxide with sodium hydroxide
• Aluminum chloride with silver nitrate
• Aluminum sulfate with barium chloride
• Aluminum oxide with hydrochloric acid

Correct Answer: Aluminum hydroxide with sodium hydroxide

Q13. Which statement about potash alum’s pH when dissolved in water is most accurate?

• Solutions are slightly acidic due to hydrolysis of aluminum ions
• Solutions are strongly basic
• Solutions are strongly alkaline
• Solutions are strongly neutral (pH 7 with no change)

Correct Answer: Solutions are slightly acidic due to hydrolysis of aluminum ions

Q14. Potash alum’s antimicrobial effect is primarily due to:

• Protein denaturation and ionic toxicity to microbes
• Direct DNA intercalation
• Targeted inhibition of bacterial ribosomes
• Acting as a broad-spectrum antibiotic

Correct Answer: Protein denaturation and ionic toxicity to microbes

Q15. Which of the following is a disadvantage or limitation of potash alum in topical use?

• Local irritation and potential mucosal sloughing at high concentrations
• High systemic bioavailability causing organ toxicity at therapeutic topical doses
• Complete lack of antimicrobial activity
• Strong systemic anticoagulant effect

Correct Answer: Local irritation and potential mucosal sloughing at high concentrations

Q16. In quality control, loss on drying for potash alum indicates:

• Water of crystallization and moisture content
• Amount of sulfates present
• Percentage of potassium impurities
• Presence of organic contaminants

Correct Answer: Water of crystallization and moisture content

Q17. Which of these astringents is inorganic and often compared with potash alum in pharmacy?

• Zinc sulfate
• Tannic acid
• Calamine (zinc oxide base)
• Alcohol

Correct Answer: Zinc sulfate

Q18. Potash alum’s official name in many pharmacopeias is often listed under:

• Alum, potash
• Potassium sulfate
• Aluminum chloride
• Potassium chloride

Correct Answer: Alum, potash

Q19. Which of the following is a correct safety measure when handling potash alum in a pharmaceutical lab?

• Use gloves and eye protection to avoid skin and eye irritation
• Inhale dust to test identity
• Store with strong acids in open containers
• Dispose by pouring down sink without neutralization

Correct Answer: Use gloves and eye protection to avoid skin and eye irritation

Q20. Which analytical technique is commonly used to determine sulfate content in potash alum samples?

• Gravimetric precipitation as barium sulfate
• Gas chromatography with flame ionization
• Thin layer chromatography for organics
• Nuclear magnetic resonance for sulfates

Correct Answer: Gravimetric precipitation as barium sulfate

Q21. In a topical gargle formulation, potash alum is used primarily for:

• Reducing mucosal inflammation and bleeding
• Providing systemic analgesia
• Acting as an anesthetic for deep tissues
• Enhancing systemic absorption of antibiotics

Correct Answer: Reducing mucosal inflammation and bleeding

Q22. Which of the following is an organic astringent often taught alongside potash alum?

• Tannic acid
• Sodium chloride
• Magnesium sulfate
• Calcium carbonate

Correct Answer: Tannic acid

Q23. Potash alum crystals are typically described as:

• Octahedral transparent crystals
• Amorphous powder only
• Fibrous and oily crystals
• Metallic flakes

Correct Answer: Octahedral transparent crystals

Q24. Which of the following reactions will produce a white gelatinous precipitate when sodium hydroxide is added to a potash alum solution?

• Formation of aluminum hydroxide
• Formation of potassium hydroxide precipitate
• Formation of sulfate precipitate
• Formation of barium sulfate

Correct Answer: Formation of aluminum hydroxide

Q25. In comparison to tannic acid, potash alum’s astringent action is mainly:

• Inorganic ionic protein coagulation
• Hydrophobic precipitation of proteins
• Enzymatic inhibition like tannic acid
• Lipid membrane disruption only

Correct Answer: Inorganic ionic protein coagulation

Q26. Which storage condition is most appropriate for potash alum in the pharmacy?

• Cool, dry place in a tightly closed container
• Warm, humid area exposed to sunlight
• Open container in a wet environment
• Mixed with strong bases for stability

Correct Answer: Cool, dry place in a tightly closed container

Q27. Potash alum can be used in combination with which ingredient to make a styptic pencil?

• Glycerin and a binder to form a solid tip
• Systemic anticoagulants like warfarin
• Oral sucrose for taste
• Liquid paraffin for injection

Correct Answer: Glycerin and a binder to form a solid tip

Q28. Which of the following pharmacopoeial tests would check the purity related to heavy metals for potash alum?

• Limit test for heavy metals
• pH meter reading only
• Flame photometry for sodium exclusively
• Viscosity measurement

Correct Answer: Limit test for heavy metals

Q29. Which clinical application uses potash alum commonly in ENT practice?

• Control of minor nasal mucosal bleeding (epistaxis)
• Systemic treatment for infections
• Long-term oral therapy for ulcers
• Intravenous hemostasis

Correct Answer: Control of minor nasal mucosal bleeding (epistaxis)

Q30. What is a likely effect of mixing potash alum with strong alkali in a formulation?

• Decomposition of alum and loss of astringent activity
• Enhanced astringent potency without change
• Conversion to an organic astringent
• Formation of harmless inert oil

Correct Answer: Decomposition of alum and loss of astringent activity

Q31. The presence of potassium in potash alum can be detected by which analytical technique?

• Flame photometry showing characteristic potassium emission
• Infrared spectroscopy for organics
• Thin layer chromatography for metals
• Mass spectrometry for polymers

Correct Answer: Flame photometry showing characteristic potassium emission

Q32. Why is potash alum not typically used for deep wound healing?

• It causes excessive tissue coagulation and irritation when used deeply
• It promotes systemic healing too rapidly
• It has no protein-precipitating activity
• It is a strong systemic antibiotic unsuitable topically

Correct Answer: It causes excessive tissue coagulation and irritation when used deeply

Q33. Which pharmacological property of potash alum contributes to odor control in deodorants?

• Antimicrobial activity reducing bacterial breakdown of sweat
• Systemic hormone modulation
• Increase in sweat production
• Neutralization of amino acids systemically

Correct Answer: Antimicrobial activity reducing bacterial breakdown of sweat

Q34. Which adverse reaction should be considered with topical potash alum use?

• Contact dermatitis or allergic reaction in sensitive individuals
• Severe systemic hypertension after topical use
• Immediate renal failure after single topical application
• Permanent loss of vision with topical skin application

Correct Answer: Contact dermatitis or allergic reaction in sensitive individuals

Q35. In the pharmaceutical lab, recrystallization of potash alum is best achieved by:

• Dissolving in hot water then cooling slowly to obtain pure crystals
• Using organic solvents like hexane at room temperature
• Heating with strong acids until dry
• Mixing with oils to precipitate crystals

Correct Answer: Dissolving in hot water then cooling slowly to obtain pure crystals

Q36. What is the role of potash alum when used in topical formulations for minor cuts?

• Acts as a styptic to reduce bleeding and disinfect the site
• Provides systemic analgesia to the patient
• Enhances systemic absorption of analgesics
• Acts as a nutrient for wound tissue

Correct Answer: Acts as a styptic to reduce bleeding and disinfect the site

Q37. Which of the following correctly contrasts potash alum with ammonium alum?

• Potash alum contains potassium ion; ammonium alum contains ammonium ion
• Both have identical cations and are chemically the same
• Potash alum contains sodium while ammonium alum contains calcium
• Ammonium alum is organic whereas potash alum is metal-organic

Correct Answer: Potash alum contains potassium ion; ammonium alum contains ammonium ion

Q38. Which excipient type should be avoided in a potash alum aqueous topical formula due to possible incompatibility?

• Strong alkaline excipients that neutralize aluminum ions
• Mild neutral buffers
• Nonionic thickening agents
• Preservatives compatible with inorganic salts

Correct Answer: Strong alkaline excipients that neutralize aluminum ions

Q39. Which environmental factor can cause loss of water of crystallization from potash alum crystals?

• Heating or prolonged exposure to dry air
• Cold humid storage
• Storage under inert gas without heat
• Submersion in nonpolar solvents

Correct Answer: Heating or prolonged exposure to dry air

Q40. In a titrimetric assay for aluminum, which complexing agent is commonly used?

• EDTA
• Acetone
• Hydrochloric acid as direct titrant
• Potassium permanganate

Correct Answer: EDTA

Q41. The use of potash alum as a deodorant mainly targets which cause of body odor?

• Bacterial degradation of sweat producing odorous compounds
• Excess epidermal cell turnover
• Excess sebum secretion only
• Systemic metabolic disorders exclusively

Correct Answer: Bacterial degradation of sweat producing odorous compounds

Q42. Which of the following is an expected physical characteristic of a pure potash alum sample?

• Colorless to white, translucent crystals
• Dark brown amorphous solid
• Oily, yellow liquid
• Magnetic metallic flakes

Correct Answer: Colorless to white, translucent crystals

Q43. Which statement is true regarding systemic absorption of potash alum from topical application?

• Systemic absorption is minimal when used topically on intact skin
• It is rapidly and extensively absorbed systemically causing major systemic effects
• It always causes hyperkalemia after topical use
• It is converted into an organic astringent in the skin

Correct Answer: Systemic absorption is minimal when used topically on intact skin

Q44. When performing a quality control test, which impurity is most directly indicated by a turbidity after barium chloride addition?

• Sulfate presence indicated by barium sulfate turbidity
• Chloride presence indicated by silver chloride
• Organic impurity indicated by cloudiness
• Metallic iron contamination indicated by color change

Correct Answer: Sulfate presence indicated by barium sulfate turbidity

Q45. Which statement about the environmental impact of alum disposal is correct?

• Disposal should avoid large releases into waterways due to sulfate and aluminum load
• It is harmless in any quantity and requires no precautions
• It neutralizes heavy metals and is beneficial to rivers
• It is a powerful organic pollutant that persists for decades

Correct Answer: Disposal should avoid large releases into waterways due to sulfate and aluminum load

Q46. For B. Pharm students, why is understanding potash alum’s crystal habit important in the lab?

• It aids in identification and purity assessment during recrystallization
• Crystal shape determines its systemic toxicity
• Crystal habit changes aroma of the compound
• It dictates whether it can be used orally for systemic therapy

Correct Answer: It aids in identification and purity assessment during recrystallization

Q47. Which of the following formulations is least appropriate for potash alum?

• Parenteral injection
• Topical lotion
• Gargle solution for oral mucosa
• Styptic pencil

Correct Answer: Parenteral injection

Q48. Potash alum’s effect on proteins can be exploited in which pharmaceutical process?

• Protein precipitation for wound contraction and hemostasis
• Increasing solubility of therapeutic peptides for oral delivery
• Breaking peptide bonds to produce amino acids
• Enhancing enzymatic digestion in formulations

Correct Answer: Protein precipitation for wound contraction and hemostasis

Q49. Which component in potash alum contributes to its ionic strength and astringent effect?

• Aluminum ion (Al3+)
• Carbonate ion (CO3 2-)
• Sodium ion (Na+)
• Chloride ion (Cl-)

Correct Answer: Aluminum ion (Al3+)

Q50. For pharmaceutical quality control, which combined observation supports the identity of potash alum?

• White octahedral crystals, positive potassium flame test, sulfate precipitation with barium chloride
• Yellow oily liquid, negative flame tests, insoluble in water
• Dark brown powder, ferrous odor, immediate dissolution in oil
• Green crystals, positive chlorine test, insoluble in hot water

Correct Answer: White octahedral crystals, positive potassium flame test, sulfate precipitation with barium chloride