05. Type of Cell
ELECTROCHEMISTRY

276249 The standard emf of $\mathrm{Zn}-\mathrm{Cu}$ voltaic cell is

1 $2.1 \mathrm{~V}$
2 $2.8 \mathrm{~V}$
3 $1.2 \mathrm{~V}$
4 $1.1 \mathrm{~V}$
ELECTROCHEMISTRY

276251 The cathode reaction in the dry cell will be

1 $\mathrm{Zn}_{(\mathrm{s})} \longrightarrow \mathrm{Zn}^{2+}+2 \mathrm{e}^{-}$
2 $\mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3}$
3 $\mathrm{Zn}(\mathrm{Hg})+2 \mathrm{OH}^{-} \longrightarrow \mathrm{ZnO}_{(\mathrm{s})}+\mathrm{H}_{2} \mathrm{O}+2 \mathrm{e}$
4 $\mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3} \longrightarrow \mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+2 \mathrm{e}$
ELECTROCHEMISTRY

276260 Which metal is protected from corrosion by a layer of its own oxide?

1 $\mathrm{Tl}$
2 $\mathrm{Ag}$
3 $\mathrm{Al}$
4 $\mathrm{Au}$
ELECTROCHEMISTRY

276261 During charging of lead storage battery, the reaction occurring at the cathode is

1 $\mathrm{Pb}^{2+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Pb}$
2 $\mathrm{Pb} \longrightarrow \mathrm{Pb}^{2+}+2 \mathrm{e}^{-}$
3 $\mathrm{PbSO}_{4}+2 \mathrm{H}_{2} \mathrm{O} \longrightarrow 2 \mathrm{PbO}_{2}+4 \mathrm{H}^{+}+\mathrm{SO}_{4}^{2-}+2 \mathrm{e}^{-}$
4 $\mathrm{Pb}^{2+}+\mathrm{SO}_{4}^{2-} \longrightarrow \mathrm{PbSO}_{4}$
ELECTROCHEMISTRY

276249 The standard emf of $\mathrm{Zn}-\mathrm{Cu}$ voltaic cell is

1 $2.1 \mathrm{~V}$
2 $2.8 \mathrm{~V}$
3 $1.2 \mathrm{~V}$
4 $1.1 \mathrm{~V}$
ELECTROCHEMISTRY

276251 The cathode reaction in the dry cell will be

1 $\mathrm{Zn}_{(\mathrm{s})} \longrightarrow \mathrm{Zn}^{2+}+2 \mathrm{e}^{-}$
2 $\mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3}$
3 $\mathrm{Zn}(\mathrm{Hg})+2 \mathrm{OH}^{-} \longrightarrow \mathrm{ZnO}_{(\mathrm{s})}+\mathrm{H}_{2} \mathrm{O}+2 \mathrm{e}$
4 $\mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3} \longrightarrow \mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+2 \mathrm{e}$
ELECTROCHEMISTRY

276260 Which metal is protected from corrosion by a layer of its own oxide?

1 $\mathrm{Tl}$
2 $\mathrm{Ag}$
3 $\mathrm{Al}$
4 $\mathrm{Au}$
ELECTROCHEMISTRY

276261 During charging of lead storage battery, the reaction occurring at the cathode is

1 $\mathrm{Pb}^{2+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Pb}$
2 $\mathrm{Pb} \longrightarrow \mathrm{Pb}^{2+}+2 \mathrm{e}^{-}$
3 $\mathrm{PbSO}_{4}+2 \mathrm{H}_{2} \mathrm{O} \longrightarrow 2 \mathrm{PbO}_{2}+4 \mathrm{H}^{+}+\mathrm{SO}_{4}^{2-}+2 \mathrm{e}^{-}$
4 $\mathrm{Pb}^{2+}+\mathrm{SO}_{4}^{2-} \longrightarrow \mathrm{PbSO}_{4}$
ELECTROCHEMISTRY

276249 The standard emf of $\mathrm{Zn}-\mathrm{Cu}$ voltaic cell is

1 $2.1 \mathrm{~V}$
2 $2.8 \mathrm{~V}$
3 $1.2 \mathrm{~V}$
4 $1.1 \mathrm{~V}$
ELECTROCHEMISTRY

276251 The cathode reaction in the dry cell will be

1 $\mathrm{Zn}_{(\mathrm{s})} \longrightarrow \mathrm{Zn}^{2+}+2 \mathrm{e}^{-}$
2 $\mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3}$
3 $\mathrm{Zn}(\mathrm{Hg})+2 \mathrm{OH}^{-} \longrightarrow \mathrm{ZnO}_{(\mathrm{s})}+\mathrm{H}_{2} \mathrm{O}+2 \mathrm{e}$
4 $\mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3} \longrightarrow \mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+2 \mathrm{e}$
ELECTROCHEMISTRY

276260 Which metal is protected from corrosion by a layer of its own oxide?

1 $\mathrm{Tl}$
2 $\mathrm{Ag}$
3 $\mathrm{Al}$
4 $\mathrm{Au}$
ELECTROCHEMISTRY

276261 During charging of lead storage battery, the reaction occurring at the cathode is

1 $\mathrm{Pb}^{2+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Pb}$
2 $\mathrm{Pb} \longrightarrow \mathrm{Pb}^{2+}+2 \mathrm{e}^{-}$
3 $\mathrm{PbSO}_{4}+2 \mathrm{H}_{2} \mathrm{O} \longrightarrow 2 \mathrm{PbO}_{2}+4 \mathrm{H}^{+}+\mathrm{SO}_{4}^{2-}+2 \mathrm{e}^{-}$
4 $\mathrm{Pb}^{2+}+\mathrm{SO}_{4}^{2-} \longrightarrow \mathrm{PbSO}_{4}$
ELECTROCHEMISTRY

276249 The standard emf of $\mathrm{Zn}-\mathrm{Cu}$ voltaic cell is

1 $2.1 \mathrm{~V}$
2 $2.8 \mathrm{~V}$
3 $1.2 \mathrm{~V}$
4 $1.1 \mathrm{~V}$
ELECTROCHEMISTRY

276251 The cathode reaction in the dry cell will be

1 $\mathrm{Zn}_{(\mathrm{s})} \longrightarrow \mathrm{Zn}^{2+}+2 \mathrm{e}^{-}$
2 $\mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3}$
3 $\mathrm{Zn}(\mathrm{Hg})+2 \mathrm{OH}^{-} \longrightarrow \mathrm{ZnO}_{(\mathrm{s})}+\mathrm{H}_{2} \mathrm{O}+2 \mathrm{e}$
4 $\mathrm{MnO}(\mathrm{OH})+\mathrm{NH}_{3} \longrightarrow \mathrm{MnO}_{2}+\mathrm{NH}_{4}^{+}+2 \mathrm{e}$
ELECTROCHEMISTRY

276260 Which metal is protected from corrosion by a layer of its own oxide?

1 $\mathrm{Tl}$
2 $\mathrm{Ag}$
3 $\mathrm{Al}$
4 $\mathrm{Au}$
ELECTROCHEMISTRY

276261 During charging of lead storage battery, the reaction occurring at the cathode is

1 $\mathrm{Pb}^{2+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Pb}$
2 $\mathrm{Pb} \longrightarrow \mathrm{Pb}^{2+}+2 \mathrm{e}^{-}$
3 $\mathrm{PbSO}_{4}+2 \mathrm{H}_{2} \mathrm{O} \longrightarrow 2 \mathrm{PbO}_{2}+4 \mathrm{H}^{+}+\mathrm{SO}_{4}^{2-}+2 \mathrm{e}^{-}$
4 $\mathrm{Pb}^{2+}+\mathrm{SO}_{4}^{2-} \longrightarrow \mathrm{PbSO}_{4}$