One phrase that best describes humidity is:
<u><em>Heat</em></u>
Answer:
- <em><u>Passive solar energy</u></em>
Explanation:
First of all, you must know that you if you put an egg on a sidewalk you are dealing with energy from the Sun, i.e. solar energy, while geothermal energy is energy that comes from the inner of the Earth and biomass energy comes from plant or animal material.
The term passive solar energy refers to the fact that the energy of the sun is used directly for the intended task, which in this case is to cook the egg.
The term active solar energy refers to the fact that the energy of the Sun is converted into a different form of energy and then used for your purpose. For instance, if the energy of the Sun were used to produce electricity and then this electricity used to cook the egg, you would be using an acitve solar energy.
Answer : The cell potential for this reaction is 0.50 V
Explanation :
The given cell reactions is:
The half-cell reactions are:
Oxidation half reaction (anode): 
Reduction half reaction (cathode): 
First we have to calculate the cell potential for this reaction.
Using Nernest equation :
![E_{cell}=E^o_{cell}-\frac{2.303RT}{nF}\log \frac{[Zn^{2+}]}{[Pb^{2+}]}](https://tex.z-dn.net/?f=E_%7Bcell%7D%3DE%5Eo_%7Bcell%7D-%5Cfrac%7B2.303RT%7D%7BnF%7D%5Clog%20%5Cfrac%7B%5BZn%5E%7B2%2B%7D%5D%7D%7B%5BPb%5E%7B2%2B%7D%5D%7D)
where,
F = Faraday constant = 96500 C
R = gas constant = 8.314 J/mol.K
T = room temperature = 
n = number of electrons in oxidation-reduction reaction = 2
= standard electrode potential of the cell = +0.63 V
= cell potential for the reaction = ?
![[Zn^{2+}]](https://tex.z-dn.net/?f=%5BZn%5E%7B2%2B%7D%5D)
= 3.5 M
![[Pb^{2+}]](https://tex.z-dn.net/?f=%5BPb%5E%7B2%2B%7D%5D)
= 
Now put all the given values in the above equation, we get:
Therefore, the cell potential for this reaction is 0.50 V
