37558
If dichloromethane\((DCM)\) and water\((H_2O)\) are used for differential extraction, which one of the following statements is correct?
1 \(DCM\) and \(H_2O\) would stay as lower and upper layer respectively in the \(S.F\)
2 \(DCM\) and \(H_2O\) will make turbid/colloidal mixture
3 \(DCM\) and \(H_2O\) would stay as upper and lower layer respectively in the separating funnel\((S.F)\)
4 \(DCM\) and \(H_2O\) will be miscible clearly
Explanation:
Density of \(DCM\) is higher than \(H_2O\)
PRACTICAL CHEMISTRY
37559
Nessler’s reagent is used to detect
1 \(PO_4^{3 - }\)
2 \(MnO_4^ - \)
3 \(NH_4^+\)
4 \(CrO_4^{2-}\)
Explanation:
Nessler's reagent \((K_2[HgI_4])\) is used for the detection and quantitative determination of ammonia (or \(NH_4^+\)) in solution. It given a yellow colour or broen precipitate of oxydimercuric ammonium iodide (figure) even with concentration as low as \(1\) part per million of \(NH_3\)
PRACTICAL CHEMISTRY
37561
A laboratory reagent imparts green colour to the flame. On heating with solid \(K_2Cr_2O_7\) and conc. \(H_2SO_4\) it evolves a red gas. Identify the reagent
1 \(CaCl_2\)
2 \(BaCl_2\)
3 \(CuCl_2\)
4 None of these
Explanation:
The reagent is \(BaCl_2\) which imparts green colour to flame. \(BaCl_2\) forms chromyl chloride (which is red in colour), when treated with \(K_2Cr_2O_7\) and conc. \(H_2SO_4\). $2BaC{{l}_{2}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}+3{{H}_{2}}S{{O}_{4}}\to {{K}_{2}}S{{O}_{4}}+2BaS{{O}_{4}}+\underset{\begin{smallmatrix} Chromyl\,chloride \\ (red\,gas) \end{smallmatrix}}{\mathop{2Cr{{O}_{2}}C{{l}_{2}}}}\,+3{{H}_{2}}O$
PRACTICAL CHEMISTRY
37562
Assertion : Potassium can be used in Lassaigne test Reason : Potassium reacts vigorously.
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is incorrect but the Reason is correct
4 If the Assertion is incorrect but the Reason is correc
Explanation:
Potassium is not used in Lassaigne’s test because of its higher reactivity
PRACTICAL CHEMISTRY
37563
Assertion : During test for nitrogen with Lassaigne extract on adding \(FeCl_3\) solution, sometimes a red precipitate is obtained.Reason : Sulphur is also present
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
Explanation:
Due to presence of sulphur, sodium thiocyanate is produced which produces blood red coloured precipitate with \(Fe^{3+}\) ion. \(Na + C + S + N\xrightarrow{\Delta }NaSCN\) \(F{e^{3 + }} + 3NaSCN \longrightarrow Fe{\left( {SCN} \right)_3} + 3N{a^ + }\)
37558
If dichloromethane\((DCM)\) and water\((H_2O)\) are used for differential extraction, which one of the following statements is correct?
1 \(DCM\) and \(H_2O\) would stay as lower and upper layer respectively in the \(S.F\)
2 \(DCM\) and \(H_2O\) will make turbid/colloidal mixture
3 \(DCM\) and \(H_2O\) would stay as upper and lower layer respectively in the separating funnel\((S.F)\)
4 \(DCM\) and \(H_2O\) will be miscible clearly
Explanation:
Density of \(DCM\) is higher than \(H_2O\)
PRACTICAL CHEMISTRY
37559
Nessler’s reagent is used to detect
1 \(PO_4^{3 - }\)
2 \(MnO_4^ - \)
3 \(NH_4^+\)
4 \(CrO_4^{2-}\)
Explanation:
Nessler's reagent \((K_2[HgI_4])\) is used for the detection and quantitative determination of ammonia (or \(NH_4^+\)) in solution. It given a yellow colour or broen precipitate of oxydimercuric ammonium iodide (figure) even with concentration as low as \(1\) part per million of \(NH_3\)
PRACTICAL CHEMISTRY
37561
A laboratory reagent imparts green colour to the flame. On heating with solid \(K_2Cr_2O_7\) and conc. \(H_2SO_4\) it evolves a red gas. Identify the reagent
1 \(CaCl_2\)
2 \(BaCl_2\)
3 \(CuCl_2\)
4 None of these
Explanation:
The reagent is \(BaCl_2\) which imparts green colour to flame. \(BaCl_2\) forms chromyl chloride (which is red in colour), when treated with \(K_2Cr_2O_7\) and conc. \(H_2SO_4\). $2BaC{{l}_{2}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}+3{{H}_{2}}S{{O}_{4}}\to {{K}_{2}}S{{O}_{4}}+2BaS{{O}_{4}}+\underset{\begin{smallmatrix} Chromyl\,chloride \\ (red\,gas) \end{smallmatrix}}{\mathop{2Cr{{O}_{2}}C{{l}_{2}}}}\,+3{{H}_{2}}O$
PRACTICAL CHEMISTRY
37562
Assertion : Potassium can be used in Lassaigne test Reason : Potassium reacts vigorously.
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is incorrect but the Reason is correct
4 If the Assertion is incorrect but the Reason is correc
Explanation:
Potassium is not used in Lassaigne’s test because of its higher reactivity
PRACTICAL CHEMISTRY
37563
Assertion : During test for nitrogen with Lassaigne extract on adding \(FeCl_3\) solution, sometimes a red precipitate is obtained.Reason : Sulphur is also present
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
Explanation:
Due to presence of sulphur, sodium thiocyanate is produced which produces blood red coloured precipitate with \(Fe^{3+}\) ion. \(Na + C + S + N\xrightarrow{\Delta }NaSCN\) \(F{e^{3 + }} + 3NaSCN \longrightarrow Fe{\left( {SCN} \right)_3} + 3N{a^ + }\)
37558
If dichloromethane\((DCM)\) and water\((H_2O)\) are used for differential extraction, which one of the following statements is correct?
1 \(DCM\) and \(H_2O\) would stay as lower and upper layer respectively in the \(S.F\)
2 \(DCM\) and \(H_2O\) will make turbid/colloidal mixture
3 \(DCM\) and \(H_2O\) would stay as upper and lower layer respectively in the separating funnel\((S.F)\)
4 \(DCM\) and \(H_2O\) will be miscible clearly
Explanation:
Density of \(DCM\) is higher than \(H_2O\)
PRACTICAL CHEMISTRY
37559
Nessler’s reagent is used to detect
1 \(PO_4^{3 - }\)
2 \(MnO_4^ - \)
3 \(NH_4^+\)
4 \(CrO_4^{2-}\)
Explanation:
Nessler's reagent \((K_2[HgI_4])\) is used for the detection and quantitative determination of ammonia (or \(NH_4^+\)) in solution. It given a yellow colour or broen precipitate of oxydimercuric ammonium iodide (figure) even with concentration as low as \(1\) part per million of \(NH_3\)
PRACTICAL CHEMISTRY
37561
A laboratory reagent imparts green colour to the flame. On heating with solid \(K_2Cr_2O_7\) and conc. \(H_2SO_4\) it evolves a red gas. Identify the reagent
1 \(CaCl_2\)
2 \(BaCl_2\)
3 \(CuCl_2\)
4 None of these
Explanation:
The reagent is \(BaCl_2\) which imparts green colour to flame. \(BaCl_2\) forms chromyl chloride (which is red in colour), when treated with \(K_2Cr_2O_7\) and conc. \(H_2SO_4\). $2BaC{{l}_{2}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}+3{{H}_{2}}S{{O}_{4}}\to {{K}_{2}}S{{O}_{4}}+2BaS{{O}_{4}}+\underset{\begin{smallmatrix} Chromyl\,chloride \\ (red\,gas) \end{smallmatrix}}{\mathop{2Cr{{O}_{2}}C{{l}_{2}}}}\,+3{{H}_{2}}O$
PRACTICAL CHEMISTRY
37562
Assertion : Potassium can be used in Lassaigne test Reason : Potassium reacts vigorously.
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is incorrect but the Reason is correct
4 If the Assertion is incorrect but the Reason is correc
Explanation:
Potassium is not used in Lassaigne’s test because of its higher reactivity
PRACTICAL CHEMISTRY
37563
Assertion : During test for nitrogen with Lassaigne extract on adding \(FeCl_3\) solution, sometimes a red precipitate is obtained.Reason : Sulphur is also present
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
Explanation:
Due to presence of sulphur, sodium thiocyanate is produced which produces blood red coloured precipitate with \(Fe^{3+}\) ion. \(Na + C + S + N\xrightarrow{\Delta }NaSCN\) \(F{e^{3 + }} + 3NaSCN \longrightarrow Fe{\left( {SCN} \right)_3} + 3N{a^ + }\)
37558
If dichloromethane\((DCM)\) and water\((H_2O)\) are used for differential extraction, which one of the following statements is correct?
1 \(DCM\) and \(H_2O\) would stay as lower and upper layer respectively in the \(S.F\)
2 \(DCM\) and \(H_2O\) will make turbid/colloidal mixture
3 \(DCM\) and \(H_2O\) would stay as upper and lower layer respectively in the separating funnel\((S.F)\)
4 \(DCM\) and \(H_2O\) will be miscible clearly
Explanation:
Density of \(DCM\) is higher than \(H_2O\)
PRACTICAL CHEMISTRY
37559
Nessler’s reagent is used to detect
1 \(PO_4^{3 - }\)
2 \(MnO_4^ - \)
3 \(NH_4^+\)
4 \(CrO_4^{2-}\)
Explanation:
Nessler's reagent \((K_2[HgI_4])\) is used for the detection and quantitative determination of ammonia (or \(NH_4^+\)) in solution. It given a yellow colour or broen precipitate of oxydimercuric ammonium iodide (figure) even with concentration as low as \(1\) part per million of \(NH_3\)
PRACTICAL CHEMISTRY
37561
A laboratory reagent imparts green colour to the flame. On heating with solid \(K_2Cr_2O_7\) and conc. \(H_2SO_4\) it evolves a red gas. Identify the reagent
1 \(CaCl_2\)
2 \(BaCl_2\)
3 \(CuCl_2\)
4 None of these
Explanation:
The reagent is \(BaCl_2\) which imparts green colour to flame. \(BaCl_2\) forms chromyl chloride (which is red in colour), when treated with \(K_2Cr_2O_7\) and conc. \(H_2SO_4\). $2BaC{{l}_{2}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}+3{{H}_{2}}S{{O}_{4}}\to {{K}_{2}}S{{O}_{4}}+2BaS{{O}_{4}}+\underset{\begin{smallmatrix} Chromyl\,chloride \\ (red\,gas) \end{smallmatrix}}{\mathop{2Cr{{O}_{2}}C{{l}_{2}}}}\,+3{{H}_{2}}O$
PRACTICAL CHEMISTRY
37562
Assertion : Potassium can be used in Lassaigne test Reason : Potassium reacts vigorously.
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is incorrect but the Reason is correct
4 If the Assertion is incorrect but the Reason is correc
Explanation:
Potassium is not used in Lassaigne’s test because of its higher reactivity
PRACTICAL CHEMISTRY
37563
Assertion : During test for nitrogen with Lassaigne extract on adding \(FeCl_3\) solution, sometimes a red precipitate is obtained.Reason : Sulphur is also present
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
Explanation:
Due to presence of sulphur, sodium thiocyanate is produced which produces blood red coloured precipitate with \(Fe^{3+}\) ion. \(Na + C + S + N\xrightarrow{\Delta }NaSCN\) \(F{e^{3 + }} + 3NaSCN \longrightarrow Fe{\left( {SCN} \right)_3} + 3N{a^ + }\)
37558
If dichloromethane\((DCM)\) and water\((H_2O)\) are used for differential extraction, which one of the following statements is correct?
1 \(DCM\) and \(H_2O\) would stay as lower and upper layer respectively in the \(S.F\)
2 \(DCM\) and \(H_2O\) will make turbid/colloidal mixture
3 \(DCM\) and \(H_2O\) would stay as upper and lower layer respectively in the separating funnel\((S.F)\)
4 \(DCM\) and \(H_2O\) will be miscible clearly
Explanation:
Density of \(DCM\) is higher than \(H_2O\)
PRACTICAL CHEMISTRY
37559
Nessler’s reagent is used to detect
1 \(PO_4^{3 - }\)
2 \(MnO_4^ - \)
3 \(NH_4^+\)
4 \(CrO_4^{2-}\)
Explanation:
Nessler's reagent \((K_2[HgI_4])\) is used for the detection and quantitative determination of ammonia (or \(NH_4^+\)) in solution. It given a yellow colour or broen precipitate of oxydimercuric ammonium iodide (figure) even with concentration as low as \(1\) part per million of \(NH_3\)
PRACTICAL CHEMISTRY
37561
A laboratory reagent imparts green colour to the flame. On heating with solid \(K_2Cr_2O_7\) and conc. \(H_2SO_4\) it evolves a red gas. Identify the reagent
1 \(CaCl_2\)
2 \(BaCl_2\)
3 \(CuCl_2\)
4 None of these
Explanation:
The reagent is \(BaCl_2\) which imparts green colour to flame. \(BaCl_2\) forms chromyl chloride (which is red in colour), when treated with \(K_2Cr_2O_7\) and conc. \(H_2SO_4\). $2BaC{{l}_{2}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}+3{{H}_{2}}S{{O}_{4}}\to {{K}_{2}}S{{O}_{4}}+2BaS{{O}_{4}}+\underset{\begin{smallmatrix} Chromyl\,chloride \\ (red\,gas) \end{smallmatrix}}{\mathop{2Cr{{O}_{2}}C{{l}_{2}}}}\,+3{{H}_{2}}O$
PRACTICAL CHEMISTRY
37562
Assertion : Potassium can be used in Lassaigne test Reason : Potassium reacts vigorously.
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is incorrect but the Reason is correct
4 If the Assertion is incorrect but the Reason is correc
Explanation:
Potassium is not used in Lassaigne’s test because of its higher reactivity
PRACTICAL CHEMISTRY
37563
Assertion : During test for nitrogen with Lassaigne extract on adding \(FeCl_3\) solution, sometimes a red precipitate is obtained.Reason : Sulphur is also present
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
Explanation:
Due to presence of sulphur, sodium thiocyanate is produced which produces blood red coloured precipitate with \(Fe^{3+}\) ion. \(Na + C + S + N\xrightarrow{\Delta }NaSCN\) \(F{e^{3 + }} + 3NaSCN \longrightarrow Fe{\left( {SCN} \right)_3} + 3N{a^ + }\)
