37261
The alkaline earth metal that imparts apple green colour to the bunsen flame when introduced in it in the form of its chloride is
1 Barium
2 Strontium
3 Calcium
4 Magnesium
Explanation:
(a) \(B{a^{2 + }}\) imparts green colour to the flame.
PRACTICAL CHEMISTRY
37262
Which gives violet coloured bead in borax bead test
1 \(F{e^{2 + }}\)
2 \(N{i^{2 + }}\)
3 \(C{o^{2 + }}\)
4 \(M{n^{2 + }}\)
Explanation:
(d) As \(M{n^{ + 2}}\) has all it’s electrons \((5)\) unpaired in it’s \(d-\) orbital, so it’s extra stable configuration requires high excitation energy and so it gives violet colour.
PRACTICAL CHEMISTRY
37263
Sodium borate on reaction with \({H_2}S{O_4}\) (conc.) and \({C_2}{H_5}OH\) gives a compound ‘\(A\)’ which burns with green flame. The compound ‘\(A\)’ is
1 \({H_2}{B_4}{O_7}\)
2 \({\left( {{C_2}{H_5}} \right)_2}{B_4}{O_7}\)
3 \({H_3}B{O_3}\)
4 \({\left( {{C_2}{H_5}} \right)_3}B{O_3}\)
Explanation:
When borate is heated with ethanol and conc. \(H _2 SO _4\), triethyl borate is produced and these vapours will burn with a green edged flame on ignition. \(2 Na _3 BO _3+3 H _2 SO _4 \text { (conc.) } \rightarrow 3 Na _2 SO _4( aq )+2 H _3 BO _3\) \(H _3 BO _3+3 C _2 H _5 OH \rightarrow \underset{Triethyl\,\, Borate}{BO _3\left( C _2 H _5\right)_3}+3 H _2\) Thus, the green edged flame is due to Triethyl Borate.
PRACTICAL CHEMISTRY
37264
On mixing two colourless gases, a deep brown colour is observed. The gases are
1 \({N_2}O\) and \({O_2}\)
2 \(NO\) and \({O_2}\)
3 \({N_2}{O_3}\) and \({O_2}\)
4 None of these
Explanation:
(b) \(2NO + {O_2} \to \;\mathop {2N{O_2}\,\,\,\,\,\,\,\,\,}\limits_{{\rm{(Deep brown gas)}}} \)
37261
The alkaline earth metal that imparts apple green colour to the bunsen flame when introduced in it in the form of its chloride is
1 Barium
2 Strontium
3 Calcium
4 Magnesium
Explanation:
(a) \(B{a^{2 + }}\) imparts green colour to the flame.
PRACTICAL CHEMISTRY
37262
Which gives violet coloured bead in borax bead test
1 \(F{e^{2 + }}\)
2 \(N{i^{2 + }}\)
3 \(C{o^{2 + }}\)
4 \(M{n^{2 + }}\)
Explanation:
(d) As \(M{n^{ + 2}}\) has all it’s electrons \((5)\) unpaired in it’s \(d-\) orbital, so it’s extra stable configuration requires high excitation energy and so it gives violet colour.
PRACTICAL CHEMISTRY
37263
Sodium borate on reaction with \({H_2}S{O_4}\) (conc.) and \({C_2}{H_5}OH\) gives a compound ‘\(A\)’ which burns with green flame. The compound ‘\(A\)’ is
1 \({H_2}{B_4}{O_7}\)
2 \({\left( {{C_2}{H_5}} \right)_2}{B_4}{O_7}\)
3 \({H_3}B{O_3}\)
4 \({\left( {{C_2}{H_5}} \right)_3}B{O_3}\)
Explanation:
When borate is heated with ethanol and conc. \(H _2 SO _4\), triethyl borate is produced and these vapours will burn with a green edged flame on ignition. \(2 Na _3 BO _3+3 H _2 SO _4 \text { (conc.) } \rightarrow 3 Na _2 SO _4( aq )+2 H _3 BO _3\) \(H _3 BO _3+3 C _2 H _5 OH \rightarrow \underset{Triethyl\,\, Borate}{BO _3\left( C _2 H _5\right)_3}+3 H _2\) Thus, the green edged flame is due to Triethyl Borate.
PRACTICAL CHEMISTRY
37264
On mixing two colourless gases, a deep brown colour is observed. The gases are
1 \({N_2}O\) and \({O_2}\)
2 \(NO\) and \({O_2}\)
3 \({N_2}{O_3}\) and \({O_2}\)
4 None of these
Explanation:
(b) \(2NO + {O_2} \to \;\mathop {2N{O_2}\,\,\,\,\,\,\,\,\,}\limits_{{\rm{(Deep brown gas)}}} \)
37261
The alkaline earth metal that imparts apple green colour to the bunsen flame when introduced in it in the form of its chloride is
1 Barium
2 Strontium
3 Calcium
4 Magnesium
Explanation:
(a) \(B{a^{2 + }}\) imparts green colour to the flame.
PRACTICAL CHEMISTRY
37262
Which gives violet coloured bead in borax bead test
1 \(F{e^{2 + }}\)
2 \(N{i^{2 + }}\)
3 \(C{o^{2 + }}\)
4 \(M{n^{2 + }}\)
Explanation:
(d) As \(M{n^{ + 2}}\) has all it’s electrons \((5)\) unpaired in it’s \(d-\) orbital, so it’s extra stable configuration requires high excitation energy and so it gives violet colour.
PRACTICAL CHEMISTRY
37263
Sodium borate on reaction with \({H_2}S{O_4}\) (conc.) and \({C_2}{H_5}OH\) gives a compound ‘\(A\)’ which burns with green flame. The compound ‘\(A\)’ is
1 \({H_2}{B_4}{O_7}\)
2 \({\left( {{C_2}{H_5}} \right)_2}{B_4}{O_7}\)
3 \({H_3}B{O_3}\)
4 \({\left( {{C_2}{H_5}} \right)_3}B{O_3}\)
Explanation:
When borate is heated with ethanol and conc. \(H _2 SO _4\), triethyl borate is produced and these vapours will burn with a green edged flame on ignition. \(2 Na _3 BO _3+3 H _2 SO _4 \text { (conc.) } \rightarrow 3 Na _2 SO _4( aq )+2 H _3 BO _3\) \(H _3 BO _3+3 C _2 H _5 OH \rightarrow \underset{Triethyl\,\, Borate}{BO _3\left( C _2 H _5\right)_3}+3 H _2\) Thus, the green edged flame is due to Triethyl Borate.
PRACTICAL CHEMISTRY
37264
On mixing two colourless gases, a deep brown colour is observed. The gases are
1 \({N_2}O\) and \({O_2}\)
2 \(NO\) and \({O_2}\)
3 \({N_2}{O_3}\) and \({O_2}\)
4 None of these
Explanation:
(b) \(2NO + {O_2} \to \;\mathop {2N{O_2}\,\,\,\,\,\,\,\,\,}\limits_{{\rm{(Deep brown gas)}}} \)
37261
The alkaline earth metal that imparts apple green colour to the bunsen flame when introduced in it in the form of its chloride is
1 Barium
2 Strontium
3 Calcium
4 Magnesium
Explanation:
(a) \(B{a^{2 + }}\) imparts green colour to the flame.
PRACTICAL CHEMISTRY
37262
Which gives violet coloured bead in borax bead test
1 \(F{e^{2 + }}\)
2 \(N{i^{2 + }}\)
3 \(C{o^{2 + }}\)
4 \(M{n^{2 + }}\)
Explanation:
(d) As \(M{n^{ + 2}}\) has all it’s electrons \((5)\) unpaired in it’s \(d-\) orbital, so it’s extra stable configuration requires high excitation energy and so it gives violet colour.
PRACTICAL CHEMISTRY
37263
Sodium borate on reaction with \({H_2}S{O_4}\) (conc.) and \({C_2}{H_5}OH\) gives a compound ‘\(A\)’ which burns with green flame. The compound ‘\(A\)’ is
1 \({H_2}{B_4}{O_7}\)
2 \({\left( {{C_2}{H_5}} \right)_2}{B_4}{O_7}\)
3 \({H_3}B{O_3}\)
4 \({\left( {{C_2}{H_5}} \right)_3}B{O_3}\)
Explanation:
When borate is heated with ethanol and conc. \(H _2 SO _4\), triethyl borate is produced and these vapours will burn with a green edged flame on ignition. \(2 Na _3 BO _3+3 H _2 SO _4 \text { (conc.) } \rightarrow 3 Na _2 SO _4( aq )+2 H _3 BO _3\) \(H _3 BO _3+3 C _2 H _5 OH \rightarrow \underset{Triethyl\,\, Borate}{BO _3\left( C _2 H _5\right)_3}+3 H _2\) Thus, the green edged flame is due to Triethyl Borate.
PRACTICAL CHEMISTRY
37264
On mixing two colourless gases, a deep brown colour is observed. The gases are
1 \({N_2}O\) and \({O_2}\)
2 \(NO\) and \({O_2}\)
3 \({N_2}{O_3}\) and \({O_2}\)
4 None of these
Explanation:
(b) \(2NO + {O_2} \to \;\mathop {2N{O_2}\,\,\,\,\,\,\,\,\,}\limits_{{\rm{(Deep brown gas)}}} \)
