Answer: It takes 3.120 seconds for the concentration of A to decrease from 0.860 M to 0.260 M.
Explanation:
Integrated rate law for second order kinetics is given by:
k = rate constant = 
= initial concentration = 0.860 M
a= concentration left after time t = 0.260 M

Thus it takes 3.120 seconds for the concentration of A to decrease from 0.860 M to 0.260 M.
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Answer:
A
Explanation:
Iron has the ground state electronic configuration [Ar]3d64s2
Fe2+ has the electronic configuration [Ar]3d6.
In an octahedral crystal field, there are two sets of degenerate orbitals; the lower lying three t2g orbitals, and the higher level two degenerate eg orbitals. Strong field ligands cause high octahedral crystal field splitting, there by separating the two sets of degenerate orbitals by a tremendous amount of energy. This energy is much greater than the pairing energy required to pair the six electrons in three degenerate orbitals. Since CN- is a strong field ligand, it leads to pairing of six electrons in three degenerate orbitals
The answer is d. hope it helps
I believe the answer is 11, its been awhile since i was in science