A electrochemical reaction is said to be spontaneous, if
Answer 1:
Consider reaction: <span>Ni^2+ (aq) + S^2- (aq) ----> + Ni (s) + S (s)
The cell representation of above reaction is given by;
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Hence,

we know that,

and

Therefore,

= - 0.25 - (-0.47) = 0.22 v
Since,
is positive, hence cell reaction is spontaneous
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Answer 2: Consider reaction: <span>Pb^2+ (aq) +H2 (g) ----> Pb (s) +2H^+ (aq)
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The cell representation of above reaction is given by;

Hence,

we know that,

and

Therefore,

= - 0.126 - 0 = -0.126 v
Since,
is negative, hence cell reaction is non-spontaneous.....................................................................................................................
Answer 3:
Consider reaction: <span>2Ag^+ (aq) + Cr(s) ---> 2 Ag (s) +Cr^2+ (aq)
</span>
The cell representation of above reaction is given by;

Hence,

we know that,

and

Therefore,

= - 0.22 - (-0.913) = 0.693 v
Since,
is positive, hence cell reaction is spontaneous
I just know the ph is between 7 and 8
Explanation:
for immiscible liquids it is quite easy to separate and the separating funnel can be used but for miscible liquid they form a single entity and separating them is quite impossible if the differences in temperature is not considered,so in distillation the one with lower boiling point evaporates out living behind the one with high boiling point
Frenkel defect is a defect in crystalline solids in which an atom is displaced from its lattice position to an interstitial space. This creates a vacant space at the original site and an interstitial defect at the new site within the same element. This defect does not affect the chemical properties of the compound. This defect usually occur in ionic solids with large size difference between the anion and cation.
LiCl does not exhibit Frenkel defect because the size difference between the anion and the cation of the compound is very small.
C because the plant needs water to go through photosynthesis