Home
Class 11
CHEMISTRY
(a). IF both (A) and (R) are correct and...

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A).
(b). If both (A) and (R) are correct but (R) is not the correct explanation of (A).
(c). If (A) is correct, but (R) is incorrect.
(d). If (A) is incorrect, but (R) is correct.
(e) if both (A) and (R) are incorrect.
Assertion (A): In the titration of `Na_(2)CO_(3)` with HCl using methyl orange indicator the volume required at the equivalence point is twice that of the acid required using phenolphthalein indicator.
Reason (R): 2 " mol of "HCl are required for complete neutralization of one mole of `Na_(2)CO_(3)`.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reasoning question, we will analyze both the assertion (A) and the reason (R) step by step. ### Step 1: Understand the Assertion (A) **Assertion (A):** In the titration of \( \text{Na}_2\text{CO}_3 \) with HCl using methyl orange indicator, the volume required at the equivalence point is twice that of the acid required using phenolphthalein indicator. - **Explanation:** - When \( \text{Na}_2\text{CO}_3 \) is titrated with HCl, it can react in two steps: 1. The first step produces sodium bicarbonate (\( \text{NaHCO}_3 \)) and is indicated by phenolphthalein. 2. The second step produces carbonic acid (\( \text{H}_2\text{CO}_3 \)) and is indicated by methyl orange. - The first equivalence point (using phenolphthalein) requires 1 mole of HCl for every mole of \( \text{Na}_2\text{CO}_3 \), while the second equivalence point (using methyl orange) requires 2 moles of HCl for complete neutralization. ### Step 2: Understand the Reason (R) **Reason (R):** 2 moles of HCl are required for complete neutralization of one mole of \( \text{Na}_2\text{CO}_3 \). - **Explanation:** - This statement is correct because \( \text{Na}_2\text{CO}_3 \) can react with HCl in two steps, requiring 2 moles of HCl to fully neutralize it to \( \text{H}_2\text{CO}_3 \). ### Step 3: Analyze the Relationship Between (A) and (R) - Both the assertion (A) and the reason (R) are correct. - However, the reason (R) does not directly explain why the volume of HCl required at the equivalence point using methyl orange is twice that required using phenolphthalein. The correct explanation involves the different equivalence points indicated by the two indicators. ### Conclusion Based on the analysis: - **Assertion (A)** is correct. - **Reason (R)** is correct. - **However, (R) is not the correct explanation of (A)**. Thus, the correct answer is **(b)**: If both (A) and (R) are correct but (R) is not the correct explanation of (A). ---
To solve the assertion and reasoning question, we will analyze both the assertion (A) and the reason (R) step by step. ### Step 1: Understand the Assertion (A) **Assertion (A):** In the titration of \( \text{Na}_2\text{CO}_3 \) with HCl using methyl orange indicator, the volume required at the equivalence point is twice that of the acid required using phenolphthalein indicator. - **Explanation:** - When \( \text{Na}_2\text{CO}_3 \) is titrated with HCl, it can react in two steps: ...
Promotional Banner

Topper's Solved these Questions

  • STOICHIOMETRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercises Integer|16 Videos

  • STOICHIOMETRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Archives Multiple Correct|1 Videos

  • STOICHIOMETRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercises Single Correct|85 Videos

  • STATES OF MATTER

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercises (Ture False)|25 Videos

  • THERMODYNAMICS

    CENGAGE CHEMISTRY ENGLISH|Exercise Archives (Subjective)|23 Videos

Similar Questions

Explore conceptually related problems

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): Concentration of H_(2)O_(2) is expressed in volume Reason (R): Volume strength = normality xx5.6

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): H_(3)PO_(2) is mono basic acid. Reason (R): Two H-atoms are attached to pghosphorous (P).

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): IN the reaction i_(2) is a oxidant. 2S_(2)O_(3)^(2-)+I_(2)toS_(4)O_(6)^(2-)+2I^(ɵ) Reason (R): During oxidation loss of electron takes place.

(a). If both (A) and (R) are correct and (R) is the correct explanation for (A). (b). If both (A) and (R) are correct and (R) is the correct explanation for (A). (c). If (A) is correct and (R) is incorrect. (d). If (A) is incorrect and (R) is correct. ltbr. (e). If both (A) and (R) are incorrect. Q. Assertion (A): Essential oils are volatile and are isoluble in H_2O Reason (R): Essential oils are purified by steam ditillation.

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): Equivalent mass of KMnO_(4) is equal to one-fifth of its molecular mass when it acts as oxidising agent in mild basic medium. Reason (R): Oxidation number of Mn in KMnO_(4) is +7 .

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): MnO_(4)^(ɵ)+S_(2)O_(3)^(2-)underset(pH=7)toMnO_(2)+HSO_(4)^(ɵ) Reason (R): The n factor for MnO_(4)^(ɵ) and S_(2)O_(3)^(2-) ions respectively are 3 and 8.

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): When gaseous hydrocarbon are completely burnt in eudiometer tube with excess of O_(2) and after cooling there is a contraction in the volume of gases. Reason (R): The volume of H_(2)O is not considered.

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): In the titration of strong acid and strong base, phenolphthalein is used as suitable indocator. Reason (R): IN the titration of strong acid and strong base, the equivalence points lies is the pH range of (3.0-10.5) and phenolphthalein have pH range of (8.0-9.8) .

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion: 5.0 " mol of "ferrous oxalate are completely oxidised by 2.5 moles of acidic solution of K_(2)Cr_(2)O_(7) . Reason(R): n-factor of ferrous oxalate against dichromate is 3.

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A). (b). If both (A) and (R) are correct but (R) is not the correct explanation of (A). (c). If (A) is correct, but (R) is incorrect. (d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect. Q. Assertion (A): Estimation of reducing substance by the use of standard I_(2) is called iodometry. Reason (R): in the reaction I_(2)+S_(2)O_(3)^(2-)toS_(4)O_(6)^(2-)+2I^(ɵ) The n factor of S_(2)O_(3)^(2-) is one.