EMF

Q.

Which of the following reactions cannot occur?

1. $2{\mathrm{AgNO}}_3\left(\mathrm{aq}\right)+\mathrm{Fe}\left(\mathrm{s}\right)\to \mathrm{Fe}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)+2\mathrm{Ag}\left(\mathrm{s}\right)$

2. ${\mathrm{CuSO}}_4\left(\mathrm{aq}\right)+\mathrm{Zn}\left(\mathrm{s}\right)\to {\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)+\mathrm{Cu}\left(\mathrm{s}\right)$

3. ${\mathrm{CuSO}}_4\left(\mathrm{aq}\right)+2\mathrm{Ag}\left(\mathrm{s}\right)\to {\mathrm{Ag}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)+\mathrm{Cu}\left(\mathrm{s}\right)$

4. $2{\mathrm{AgNO}}_3\left(\mathrm{aq}\right)+\mathrm{Zn}\left(\mathrm{s}\right)\to \mathrm{Zn}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)+2\mathrm{Ag}\left(\mathrm{s}\right)$

Q.

A metal “A” reacts with a metallic chloride of “B” to give metal “B”. But metallic chloride of “A” cannot give metal “A” on reaction with metal “B”. What conclusion can you draw from this?

Q.

1. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
   
2. Assertion is true but Reason is false
3. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
4. Assertion is false but Reason is true
5. Both Assertion and Reason are false

Q. The spontaneous reaction that takes place in this cell is:

1. $Zn+Ni\to Z{n}^{2+}+N{i}^{2+}$
2. $Zn+N{i}^{2+}\to Z{n}^{2+}+Ni$
3. $Ni+Z{n}^{2+}\to N{i}^{2+}+Zn$
4. $N{i}^{2+}+2K\to 2K^{+}+Ni$

Q.

What is meant by activity series of metals? State which of the following reactions will take place giving the suitable reason for each.

$\mathrm{Fe}\left(\mathrm{s}\right)+\mathrm{ZnSO}{}_4(\mathrm{aq})\to \mathrm{FeSO}{}_4(\mathrm{aq})+\mathrm{Zn}\left(\mathrm{s}\right)$

Q. what is discharge potential? how is it related to electrode potential?

Q. Electrode potentials are:
${Zn}^0\to {Zn}^{2+}+2e^{-};E^0=+0.76V$
${Au}^0\to {Au}^{3+}+3e^{-};E^0=-1.42V$
What is the potential of the reaction, if a gold foil is kept in a solution containing zinc ions?

1. $-1.34$ V (no reaction)
2. $+1.34$ V (no reaction)
3. $-2.18$ V (no reaction)
4. $+2.18$ V (reaction)
5. $-0.66$ V (reaction)