Both carbon and lead belong to Group IV elements, and thus they have the same number of valence electrons.
<span>In
each of the other options, the two elements belong to different groups,
and thus they do NOT have the same number of valence electrons.
I hope this helped you, please tell me if I am correct or not <3
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The redox reaction given is,
Cu₍s₎ + 2Ag⁺₍aq₎ ---------> Cu²⁺₍aq₎ + 2Ag₍s₎
The equilibrium constant for this reaction is as follow,
Kc = [Cu²⁺][Ag]² / [Cu][Ag⁺]²
Kc = [Cu²⁺] / [Ag⁺]² ∴ {[Cu₍s₎] = 1 & [Ag₍s₎] = 1
So, Above bolded is <span>the concentration equilibrium constant expression for the given reaction.</span>
B. They work against a strong gravitational force
True, All non- zero digits are considered Significant.