Answer:
c tarnishes in air
Explanation:
After silver has been exposed to air that contains sulphur gases, discoloration would occur. there would be darkening that is caused by the reaction with gases.When any silver object tarnishes, it brings about a disfiguring of that object. Hydrogen sulphide would be needed for this to happen. silver sulphide is black and a if a thin layer should form on any surface, it ill darken it. This is what we refer to as tarnishing.
Answer:
The standard cell potential of the reaction is 0.78 Volts.
Explanation:

Reduction at cathode :
Reduction potential of
to Cu=
Oxidation at anode:

Reduction potential of
to Fe=
To calculate the
of the reaction, we use the equation:

Putting values in above equation, we get:

The standard cell potential of the reaction is 0.78 Volts.
I think it's easiest to find the pOH from the given [OH-] first.
-log(1x10^-5)
pOH=5
Then find the pH.
pOH+pH=14
5+pH=14
pH=9
Then find the [H+] using the pH.
antilog(-9) (if you dont have an antilog button use 10^-9)
[H+]=1x10^-9
The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. ... Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff.