Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Evaluate the following statements regarding indicators: Statement-I: Olfactory indicators change their odour in acidic or basic solutions. Statement-II: Clove oil is an example of an olfactory indicator.
Both I and II are correct
Only I is correct
Only II is correct
Both I and II are incorrect
Both I and II are correct
Olfactory indicators are substances whose smell changes depending on whether they are in an acidic or basic medium. Both statements are correct because clove oil, along with onion and vanilla extract, serves as a standard olfactory indicator in chemistry.
Olfactory indicators are substances whose smell changes depending on whether they are in an acidic or basic medium. Both statements are correct because clove oil, along with onion and vanilla extract, serves as a standard olfactory indicator in chemistry.
Think of a scented candle whose perfume becomes undetectable or changes drastically when you leave it in a room full of smoke; the environment (acid or base) acts like the smoke, altering your perception of the scent.
OVC: Onion, Vanilla, Clove are the olfactory indicators.
H++OHтИТтЖТH2тАЛO тАФ neutralization process in aqueous solutions
pH=тИТlog10тАЛ[H+] тАФ definition of acidity/basicity level
The principle relies on the presence of volatile aromatic compounds. When these substances interact with hydronium ions (H3тАЛO+) or hydroxide ions (OHтИТ), their chemical structure or ionization state changes, altering the way they interact with olfactory receptors in the nose, thus masking or changing the characteristic smell.
Olfactory indicators are specifically useful for visually impaired students in laboratory settings.
Onion juice loses its smell in a basic solution but retains it in an acidic solution.
Vanilla extract is a common olfactory indicator used in titration-like demonstrations.
Accessible for visually impaired individuals
Does not require specialized electronic sensors
Less precise than synthetic indicators like phenolphthalein
Affected by temperature and concentration variations
Demonstrating acid-base properties in classroom experiments
Preliminary qualitative screening for chemical acidity/basicity
The range of olfactory indicators is limited compared to chemical indicators that change color.
Option B, C, and D are incorrect because they fail to acknowledge the validity of both accurate scientific statements.
A is correct тАФ Both statements correctly describe the definition and examples of olfactory indicators used in acid-base chemistry.
Remember that while synthetic indicators like methyl orange change color, olfactory indicators are defined strictly by changes in 'smell'тАФkeep these classifications separate for your exams.