Given below are two statements:
Statement I: Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis.
Statement II: Phenolphthalein is a weak base, therefore it dissociates in acidic medium.
Statement I: Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis.
Statement II: Phenolphthalein is a weak base, therefore it dissociates in acidic medium.
- Both Statement I and Statement II are true
- Both Statement I and Statement II are false
- Statement I is true but Statement II is false
- Statement I is false but Statement II is true
The Correct Option is B
Solution and Explanation
We need to evaluate statements regarding primary standards and acid-base indicators.
Step 2: Detailed Explanation:
- Statement I: Potassium dichromate (\(K_2Cr_2O_7\)) is a primary standard because it can be obtained in high purity and is non-hygroscopic. However, Sodium dichromate (\(Na_2Cr_2O_7\)) is hygroscopic (absorbs moisture) and therefore cannot be used as a primary standard. This makes the statement false.
- Statement II: Phenolphthalein is a weak organic acid, not a base. It dissociates in basic medium to give a pink color. In acidic medium, the dissociation is suppressed by the common ion effect, remaining colorless. This makes the statement false.
Step 3: Final Answer:
Both statements are false.
Top JEE Main Chemistry Questions
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- At equilibrium the concentrations of and in a sealed vessel at . What will be for the reaction
- Find out the major products from the following reactions
Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
- The correct order of atomic radii is:
Top JEE Main Questions
- In a hydrogen like atom, when an electron jumps from the $M$ - shell to the $L$ - shell, the wavelength of emitted radiation is $\lambda$. If an electron jumps from $N$-shell to the $L$-shell, the wavelength of emitted radiation will be :
- Two masses $m$ and $\frac{m}{2}$ are connected at the two ends of a massless rigid rod of length $l$. The rod is suspended by a thin wire of torsional constant $k$ at the centre of mass of the rod-mass system(see figure). Because of torsional constant $k$, the restoring torque is $\tau =k\theta$ for angular displacement $\theta$. If the rod is rota ted by $\theta_0$ and released, the tension in it when it passes through its mean position will be:
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- The value of is
- The number of terms of an is even. The sum of the odd terms is and of the even terms is . The last term exceeds the first by . Then the number of terms in the series is ______.