JAMB - Chemistry (1980 - No. 28)
A cold aqueous solution of sodium chloride is electrolyzed using a graphite anode and an iron cathode. In the course of the electrolysis the electrolyte is continuously stirred. The liquid left after electrolysis will therefore consist of?
sodium hydroxide solution
chlorine water
pure water
sodium hypochlorite solution
hydrochloric acid solution
Wyjaśnienie
we take cold aqueous to be concentrated solution of NaCl.
NaCl → \(Na^+ + Cl^-\)
\(H_2O → H^+ + OH^-\)
H ion will be preferably discharged at the cathode while Cl ion will be discharged at the anode(due to high concentration)
Thus, NaOH is left in the solution.