321280
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \((+\mathrm{VI})\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Both Assertion and Reason is incorrect.
Explanation:
In \({\text{N}}{{\text{a}}_{\text{2}}}{\text{Cr}}{{\text{O}}_{\text{4}}}{\text{,}}\) is in +6 oxidation state with \(\mathrm{d}^{\circ}\) configuration. The \(\mathrm{CrO}_{4}^{2-}\) ions in aqueous solution give yellow colour which is not due to \(\mathrm{d}-\mathrm{d}\) transition but due to charge transfer, i.e., momentary transfer of charge from oxygen atom to metal atom. Hence, both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
AIIMS - 2013
CHXII08:THE D- & F-BLOCK ELEMENTS
321281
Potassium dichromate acts as a strong oxidising agent in acidic solution. During this process, the oxidation state changes from
1 \(+ 6\) to \(+ 3\)
2 \(+ 3\) to\(+ 1\)
3 \(+ 6\) to \(+ 2\)
4 \(+ 2\) to \(+ 1\)
Explanation:
In acidic medium, \(\stackrel{+6}{\mathrm{Cr}_{2}} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{+3}+7 \mathrm{H}_{2} \mathrm{O}\) The oxidation state changes from \(+ 6\) to \(+ 3\) .
JEE - 2023
CHXII08:THE D- & F-BLOCK ELEMENTS
321282
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \(+\mathrm{VI}\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
\(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) solution in water is yellow in colour, when acidified it changes to orange colour (due to the formation of \(\mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-}\) ions). \(2 \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow\) \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{Na}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\) Let oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}\) be x. \(\Rightarrow 2(+1)+\mathrm{x}+4(-2)=0 \Rightarrow \mathrm{x}=+6\). So option (2) is correct.
CHXII08:THE D- & F-BLOCK ELEMENTS
321283
The number of \({\mathrm{\mathrm{Cr}-\mathrm{O}-\mathrm{Cr}}}\) bonds in dichromate ion is ____ .
321280
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \((+\mathrm{VI})\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Both Assertion and Reason is incorrect.
Explanation:
In \({\text{N}}{{\text{a}}_{\text{2}}}{\text{Cr}}{{\text{O}}_{\text{4}}}{\text{,}}\) is in +6 oxidation state with \(\mathrm{d}^{\circ}\) configuration. The \(\mathrm{CrO}_{4}^{2-}\) ions in aqueous solution give yellow colour which is not due to \(\mathrm{d}-\mathrm{d}\) transition but due to charge transfer, i.e., momentary transfer of charge from oxygen atom to metal atom. Hence, both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
AIIMS - 2013
CHXII08:THE D- & F-BLOCK ELEMENTS
321281
Potassium dichromate acts as a strong oxidising agent in acidic solution. During this process, the oxidation state changes from
1 \(+ 6\) to \(+ 3\)
2 \(+ 3\) to\(+ 1\)
3 \(+ 6\) to \(+ 2\)
4 \(+ 2\) to \(+ 1\)
Explanation:
In acidic medium, \(\stackrel{+6}{\mathrm{Cr}_{2}} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{+3}+7 \mathrm{H}_{2} \mathrm{O}\) The oxidation state changes from \(+ 6\) to \(+ 3\) .
JEE - 2023
CHXII08:THE D- & F-BLOCK ELEMENTS
321282
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \(+\mathrm{VI}\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
\(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) solution in water is yellow in colour, when acidified it changes to orange colour (due to the formation of \(\mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-}\) ions). \(2 \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow\) \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{Na}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\) Let oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}\) be x. \(\Rightarrow 2(+1)+\mathrm{x}+4(-2)=0 \Rightarrow \mathrm{x}=+6\). So option (2) is correct.
CHXII08:THE D- & F-BLOCK ELEMENTS
321283
The number of \({\mathrm{\mathrm{Cr}-\mathrm{O}-\mathrm{Cr}}}\) bonds in dichromate ion is ____ .
321280
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \((+\mathrm{VI})\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Both Assertion and Reason is incorrect.
Explanation:
In \({\text{N}}{{\text{a}}_{\text{2}}}{\text{Cr}}{{\text{O}}_{\text{4}}}{\text{,}}\) is in +6 oxidation state with \(\mathrm{d}^{\circ}\) configuration. The \(\mathrm{CrO}_{4}^{2-}\) ions in aqueous solution give yellow colour which is not due to \(\mathrm{d}-\mathrm{d}\) transition but due to charge transfer, i.e., momentary transfer of charge from oxygen atom to metal atom. Hence, both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
AIIMS - 2013
CHXII08:THE D- & F-BLOCK ELEMENTS
321281
Potassium dichromate acts as a strong oxidising agent in acidic solution. During this process, the oxidation state changes from
1 \(+ 6\) to \(+ 3\)
2 \(+ 3\) to\(+ 1\)
3 \(+ 6\) to \(+ 2\)
4 \(+ 2\) to \(+ 1\)
Explanation:
In acidic medium, \(\stackrel{+6}{\mathrm{Cr}_{2}} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{+3}+7 \mathrm{H}_{2} \mathrm{O}\) The oxidation state changes from \(+ 6\) to \(+ 3\) .
JEE - 2023
CHXII08:THE D- & F-BLOCK ELEMENTS
321282
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \(+\mathrm{VI}\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
\(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) solution in water is yellow in colour, when acidified it changes to orange colour (due to the formation of \(\mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-}\) ions). \(2 \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow\) \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{Na}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\) Let oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}\) be x. \(\Rightarrow 2(+1)+\mathrm{x}+4(-2)=0 \Rightarrow \mathrm{x}=+6\). So option (2) is correct.
CHXII08:THE D- & F-BLOCK ELEMENTS
321283
The number of \({\mathrm{\mathrm{Cr}-\mathrm{O}-\mathrm{Cr}}}\) bonds in dichromate ion is ____ .
321280
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \((+\mathrm{VI})\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Both Assertion and Reason is incorrect.
Explanation:
In \({\text{N}}{{\text{a}}_{\text{2}}}{\text{Cr}}{{\text{O}}_{\text{4}}}{\text{,}}\) is in +6 oxidation state with \(\mathrm{d}^{\circ}\) configuration. The \(\mathrm{CrO}_{4}^{2-}\) ions in aqueous solution give yellow colour which is not due to \(\mathrm{d}-\mathrm{d}\) transition but due to charge transfer, i.e., momentary transfer of charge from oxygen atom to metal atom. Hence, both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
AIIMS - 2013
CHXII08:THE D- & F-BLOCK ELEMENTS
321281
Potassium dichromate acts as a strong oxidising agent in acidic solution. During this process, the oxidation state changes from
1 \(+ 6\) to \(+ 3\)
2 \(+ 3\) to\(+ 1\)
3 \(+ 6\) to \(+ 2\)
4 \(+ 2\) to \(+ 1\)
Explanation:
In acidic medium, \(\stackrel{+6}{\mathrm{Cr}_{2}} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{+3}+7 \mathrm{H}_{2} \mathrm{O}\) The oxidation state changes from \(+ 6\) to \(+ 3\) .
JEE - 2023
CHXII08:THE D- & F-BLOCK ELEMENTS
321282
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \(+\mathrm{VI}\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
\(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) solution in water is yellow in colour, when acidified it changes to orange colour (due to the formation of \(\mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-}\) ions). \(2 \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow\) \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{Na}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\) Let oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}\) be x. \(\Rightarrow 2(+1)+\mathrm{x}+4(-2)=0 \Rightarrow \mathrm{x}=+6\). So option (2) is correct.
CHXII08:THE D- & F-BLOCK ELEMENTS
321283
The number of \({\mathrm{\mathrm{Cr}-\mathrm{O}-\mathrm{Cr}}}\) bonds in dichromate ion is ____ .
321280
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \((+\mathrm{VI})\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Both Assertion and Reason is incorrect.
Explanation:
In \({\text{N}}{{\text{a}}_{\text{2}}}{\text{Cr}}{{\text{O}}_{\text{4}}}{\text{,}}\) is in +6 oxidation state with \(\mathrm{d}^{\circ}\) configuration. The \(\mathrm{CrO}_{4}^{2-}\) ions in aqueous solution give yellow colour which is not due to \(\mathrm{d}-\mathrm{d}\) transition but due to charge transfer, i.e., momentary transfer of charge from oxygen atom to metal atom. Hence, both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
AIIMS - 2013
CHXII08:THE D- & F-BLOCK ELEMENTS
321281
Potassium dichromate acts as a strong oxidising agent in acidic solution. During this process, the oxidation state changes from
1 \(+ 6\) to \(+ 3\)
2 \(+ 3\) to\(+ 1\)
3 \(+ 6\) to \(+ 2\)
4 \(+ 2\) to \(+ 1\)
Explanation:
In acidic medium, \(\stackrel{+6}{\mathrm{Cr}_{2}} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{+3}+7 \mathrm{H}_{2} \mathrm{O}\) The oxidation state changes from \(+ 6\) to \(+ 3\) .
JEE - 2023
CHXII08:THE D- & F-BLOCK ELEMENTS
321282
Assertion : Solution of \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) in water is intensely coloured. Reason : Oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) is \(+\mathrm{VI}\).
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
\(\mathrm{Na}_{2} \mathrm{CrO}_{4}\) solution in water is yellow in colour, when acidified it changes to orange colour (due to the formation of \(\mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-}\) ions). \(2 \mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow\) \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{Na}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\) Let oxidation state of \(\mathrm{Cr}\) in \(\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{4}\) be x. \(\Rightarrow 2(+1)+\mathrm{x}+4(-2)=0 \Rightarrow \mathrm{x}=+6\). So option (2) is correct.
CHXII08:THE D- & F-BLOCK ELEMENTS
321283
The number of \({\mathrm{\mathrm{Cr}-\mathrm{O}-\mathrm{Cr}}}\) bonds in dichromate ion is ____ .
