Olfactory indicators with examples and their changes when react with acid or base.

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Olfactory indicators are substances that have a distinctive odor that changes when they react with acids or bases. This change in odor is used to identify the type of substance, whether it is acidic, neutral, or basic. Here are some examples of olfactory indicators and how they change when they react with acids or bases:

Lemon juice: Lemon juice has a strong citrus odor, and it is acidic in nature. When lemon juice reacts with a base, its odor changes to a sweeter, less sour smell.
Vinegar: Vinegar has a sharp, sour odor, and it is acidic in nature. When vinegar reacts with a base, its odor changes to a milder, less sour smell.
Baking soda: Baking soda has a mild, slightly salty odor, and it is basic in nature. When baking soda reacts with an acid, its odor changes to a stronger, more alkaline smell.
Ammonia: Ammonia has a strong, pungent odor, and it is basic in nature. When ammonia reacts with an acid, its odor changes to a milder, less pungent smell.

It's important to note that these changes in odor can be subtle and may not be easily noticeable in some cases. However, these changes can be used as a simple test to identify the type of substance and its pH level.

Olfactory indicators

Olfactory Indicators

Also check:

Relevant Concepts
Acids, Bases and Salts	Acid Strength	Examples of Weak Acids
Experiments on Properties of Acids and Bases	Definition and Examples of Bases in Everyday Life	Neutralization

CBSE CLASS XII Related Questions

1.
(i) Why do Zr and Hf exhibit similar properties ?
(ii) "\( E^\circ \) for \( \mathrm{Mn^{3+}/Mn^{2+}} \) couple is more positive than that for \( \mathrm{Fe^{3+}/Fe^{2+}} \)." Justify the statement.
[Atomic number : Mn = 25, Fe = 26]

View Solution

2.
(i) Give a chemical test to distinguish between Propanal and Propanone.
(ii) Which of the given acids is stronger and why ? \( \mathrm{F_3C{-}C_6H_4{-}COOH} \) or \( \mathrm{H_3C{-}C_6H_4{-}COOH} \)
(iii) Complete the given reaction sequence :
\[ \mathrm{CH_3CH_2CH_2COOC_2H_5} \xrightarrow{\mathrm{NaOH}} \mathrm{A + C_2H_5OH} \]
\[ \mathrm{A} \xrightarrow{\mathrm{H_3O^+}} \mathrm{B} \]

View Solution

3.
(a) Write two structural differences between DNA and RNA.
(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.
(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

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4.
Consider the decomposition of hydrogen peroxide \( (\mathrm{H_2O_2}) \) as per the equation given below : \[ 2\mathrm{H_2O_2} \xrightarrow[\text{Alkaline medium}]{I^-} 2\mathrm{H_2O} + \mathrm{O_2} \] The mechanism for this reaction was found to be : Step I : \( \mathrm{H_2O_2} + I^- \longrightarrow \mathrm{H_2O} + IO^- \) (slow) Step II : \( \mathrm{H_2O_2} + IO^- \longrightarrow \mathrm{H_2O} + I^- + \mathrm{O_2} \) (fast) (a) Write the rate law expression. (b) Determine the order of reaction with respect to \( \mathrm{H_2O_2} \), \( I^- \) and overall order of reaction. (c) What is the molecularity of the reaction in Step II ?

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5.
From the given data of \(E^{\circ}\) values, answer the following questions :
(I) Why \(E^{\circ}_{M^{2+}/M}\) show irregular trend in the above values ?
(II) Why is \(E^{\circ}_{Cu^{2+}/Cu}\) value exceptionally positive ?
(III) Why \(E^{\circ}_{Mn^{2+}/Mn}\) value is highly negative ?

View Solution

6.
A reaction \( \mathrm{A \rightarrow B} \) follows second order kinetics. How will the rate of reaction be affected if the concentration of (i) A is increased by three times, and (ii) A is reduced to half ?

View Solution

Olfactory indicators with examples and their changes when react with acid or base.

CBSE CLASS XII Related Questions

1.
(i) Why do Zr and Hf exhibit similar properties ?
(ii) "\( E^\circ \) for \( \mathrm{Mn^{3+}/Mn^{2+}} \) couple is more positive than that for \( \mathrm{Fe^{3+}/Fe^{2+}} \)." Justify the statement.
[Atomic number : Mn = 25, Fe = 26]

3.
(a) Write two structural differences between DNA and RNA.
(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.
(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

5.
From the given data of \(E^{\circ}\) values, answer the following questions :
(I) Why \(E^{\circ}_{M^{2+}/M}\) show irregular trend in the above values ?
(II) Why is \(E^{\circ}_{Cu^{2+}/Cu}\) value exceptionally positive ?
(III) Why \(E^{\circ}_{Mn^{2+}/Mn}\) value is highly negative ?

6.
A reaction \( \mathrm{A \rightarrow B} \) follows second order kinetics. How will the rate of reaction be affected if the concentration of (i) A is increased by three times, and (ii) A is reduced to half ?

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Olfactory indicators with examples and their changes when react with acid or base.

CBSE CLASS XII Related Questions

1.(i) Why do Zr and Hf exhibit similar properties ?(ii) "\( E^\circ \) for \( \mathrm{Mn^{3+}/Mn^{2+}} \) couple is more positive than that for \( \mathrm{Fe^{3+}/Fe^{2+}} \)." Justify the statement.[Atomic number : Mn = 25, Fe = 26]

3.(a) Write two structural differences between DNA and RNA.(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

5.From the given data of \(E^{\circ}\) values, answer the following questions : (I) Why \(E^{\circ}_{M^{2+}/M}\) show irregular trend in the above values ? (II) Why is \(E^{\circ}_{Cu^{2+}/Cu}\) value exceptionally positive ? (III) Why \(E^{\circ}_{Mn^{2+}/Mn}\) value is highly negative ?

6.A reaction \( \mathrm{A \rightarrow B} \) follows second order kinetics. How will the rate of reaction be affected if the concentration of (i) A is increased by three times, and (ii) A is reduced to half ?

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
(i) Why do Zr and Hf exhibit similar properties ?
(ii) "\( E^\circ \) for \( \mathrm{Mn^{3+}/Mn^{2+}} \) couple is more positive than that for \( \mathrm{Fe^{3+}/Fe^{2+}} \)." Justify the statement.
[Atomic number : Mn = 25, Fe = 26]

3.
(a) Write two structural differences between DNA and RNA.
(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.
(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

5.
From the given data of \(E^{\circ}\) values, answer the following questions :
(I) Why \(E^{\circ}_{M^{2+}/M}\) show irregular trend in the above values ?
(II) Why is \(E^{\circ}_{Cu^{2+}/Cu}\) value exceptionally positive ?
(III) Why \(E^{\circ}_{Mn^{2+}/Mn}\) value is highly negative ?

6.
A reaction \( \mathrm{A \rightarrow B} \) follows second order kinetics. How will the rate of reaction be affected if the concentration of (i) A is increased by three times, and (ii) A is reduced to half ?