When the following oxidation-reduction reaction in acidic solution is balanced,
ID: 517518 • Letter: W
Question
When the following oxidation-reduction reaction in acidic solution is balanced, what is lowest whole-number coefficient for K^+ (aq)? A) 1 B) 2 C) 3 D) 4 E) 5 When the following oxidation-reduction reaction in acidic solution is balanced, what is the lowest whole-number coefficient for H^+, and on which side of the balanced equation should it appear? Cr_2O^2-_7(aq) + CH_2O(aq) rightarrow Cr^3+(aq) + HCOOH(aq) A) 1, reactant side B) 2, product side C) 6, product side D) 8, reactant side E) 14, reactant side When the following reaction in basic solution is balanced, what is the lowest whole-number coefficient for OH^-? Fe(OH)_2(s) + H_2(g) rightarrow Fe(s) + H_2O(l) A) 0 B) 1 C) 2 D) 3 E) 4.Explanation / Answer
Ans 21 . B. 2
The balanced reaction will be
2K + Cu2+ ---> 2K+ + Cu
The 2 electrons accepted by copper divalent cation to get reduced to copper metal comes from 2 atoms of potassium , as potassium is a single valent atom