Explanation:
Reduction is a chemical reaction in which electrons are gained by one of the atoms taking part in the reaction and lowering of an oxidation state of that atom.
Reduction takes place at the cathode.
In aqueous, vanadium(V) is present in +5 oxidation state which on reduction changes to vanadium(I) with +1 oxidation state.
The half reaction is :

Answer:
option B is correct : The beam was positively charged.
Explanation:
In 19th century J.J Thomson conducted an experiment on cathode ray tube. These cathode ray tubes were sealed glass tubes inside which the pressure of the gas reduced by evacuating air. Then he applied a high voltage across two electrodes at end of the tube, that voltage caused a beam of particles to flow from the cathode to the anode.
Beam of the particles were originated at the cathode and detected on anode by a phosphorous beyond the anode. As at that time phosphorous sparks and emit light.
To test properties of particles he places two opposite charged electric plates around the cathode rays that is one negative and one positive plate.
Thomson observed that these rays deflected to positive electric plate so it indicated that these rays are composed of negatively charged particles as it was attracted by the positive charged electric plate. These particles later named as electrons.
So,
option B is correct : The beam was positively charged.
Answer:
The volume of HCl required is 
Explanation:
From the question we are told that
The chemical equation for this reaction is

The mass of Al is 
The concentration of HCl is 
The number of moles of
given is 
The molar mass of Al is 
So


From the balanced equation
2 moles of Al reacts with 6 moles of HCl
So 0.07 moles of Al will react with x
Therefore


Now the volume of HCl can be obtained as

So 
