Answer: Gold act as cathode.
Explanation:
Standard potential for an electrochemical cell is given by:
= standard electrode potential =
The 
values have to be reduction potentials.
Reduction potentials for given elements
The element Be with negative reduction potential will lose electrons undergo oxidation and thus act as anode.The element Au with positive reduction potential will gain electrons undergo reduction and thus acts as cathode.
Cathode : 
Anode : 
Thus gold act as cathode.
Answer:
The pH of an aqueous solution is the measure of how acidic or basic it is. The pH of an aqueous solution can be determined and calculated by using the concentration of hydronium ion concentration in the solution.
Explanation:
(a) We know that work is the product of Force and Distance so: (in this
case Distance is negative since going down so –d)
work = force * distance
work = M * (g - g/4) * -d
work = -3Mgd/4 <span>
(b) The work by the weight of the block is simply:</span>
work = Mgd <span>
(c) The kinetic energy is simply equivalent to the
net work, therefore:</span>
KE = net work
KE = Mgd/4 <span>
(d) The velocity is:</span>
v = √(2*KE/M)
Plugging in the value of KE from c:
v = √(2*Mgd / 4M)
<span>v = √(gd / 2) </span>
Balanced equation:
Ca(OH)2+H2SO4=CaSO4+2 H20<span />
