alright last qns for the day or first qns of the exam day depending on when you come back.
1) In the electrolysis of copper (ii) sulphate between platinum electrodes, pls confirm that the mass of negative electrode remains the same.
2) When ammonia and oxygen is passed over a hot platinum wire, the wire continues to glow. How does this indicate that platinum is a catalyst. Also, how is this in syllabus? lol
ill check this at mid night and early in the morning. XD
its 12.01. Good luck to all o lvlers the exam is today! And hope i can get full marks!
Originally posted by davidche:alright last qns for the day or first qns of the exam day depending on when you come back.
1) In the electrolysis of copper (ii) sulphate between platinum electrodes, pls confirm that the mass of negative electrode remains the same.
2) When ammonia and oxygen is passed over a hot platinum wire, the wire continues to glow. How does this indicate that platinum is a catalyst. Also, how is this in syllabus? lol
1) Since this is an electrolytic cell, the 'negative' electrode refers to the cathode (it's negatively charged because lots of electrons from the battery is flowing towards there). Since it's the cathode, reduction occurs. What can be reduced? Platinum metal is already in reduced form. So it must be a cation from solution. The cation with the highest concentration is H+. Hence protons (H+) are reduced at the cathode to H2 gas. Mass of cathode remains same.
2) Not in syllabus.
Thanks alot.