Which is anode and which is cathode? - Chemistry Stack Exchange
2017年2月15日 · Designation of anode and cathode. So labeling the anode and the cathode relies on an analogy between a voltaic cell and a photovoltaic cell as a source of electrical work. It makes sense to use the direction of electron flow in the external circuit to define anode and cathode (electrons flow from anode to cathode in the external circuit).
Half cells: difference between E (cell) = E (cathode}-E (anode) & E ...
The cathode is actually the reduction step, and the anode is the oxidation step. A useful mnemonic I learned from my chemistry professor is a red cat and an ox. Interestingly, cathodes in electrochemical cells are red and are positive. So I have found many uses for this along the way.
Positive or Negative Anode/Cathode in Electrolytic/Galvanic Cell
2014年9月27日 · In a galvanic (voltaic) cell, the anode is considered negative and the cathode is considered positive. This seems reasonable as the anode is the source of electrons and cathode is where the electrons flow. However, in an electrolytic cell, the anode is taken to be positive while the cathode is now negative.
How are cathode rays produced? - Chemistry Stack Exchange
2014年10月28日 · Cathode rays are just a beam of electron observed in vaccum tube. when the dicharge tube or evacuated glass tube is facilitated with 2 electrode and with high voltage, due to emmission of electron from and travelling in perpendicular to cathode,glass opposite of negative electrode(ie cathode) is observed to glow.
electrochemistry - Cathode + Anode - Chemistry Stack Exchange
2014年5月15日 · During discharge, the ions flow from the anode to the cathode through the electrolyte and separator; charge reverses the direction and the ions flow from the cathode to the anode. On discharge, the anode undergoes oxidation, or loss of electrons, and the cathode sees a reduction, or a gain of electrons. Charge reverses the movement.
Direction of flow of current in electrolytic cell [duplicate]
2017年9月13日 · So in both cases electrons flow from the anode to the cathode. (This analysis is complicated by something I learnt in school as the technical current flow definition. According to Bavarian textbooks, technicians defined current as flowing from plus to minus which is exactly the opposite of the flow of electrons.
physical chemistry - How to correctly define anode and cathode ...
The cathode is a negatively charged electrode where reduction takes place, and the anode is a positively charged electrode where oxidation takes place. Let's analyse the second cell. Without any additional information, I assume that no external power source is connected.
Why do positive ions go to the cathode? - Chemistry Stack Exchange
2017年7月4日 · The cathode is a positive electrode in a galvanic cell. There are different notations for the sign (±) of the cathode used in the literature, which are determined, in particular, by the nature of the process. A very broad definition of a cathode is that it is the electrode of some device connected to the negative pole of the current source.
electrons - How did J. J. Thomson prove that the cathode rays …
2018年12月11日 · Cathode "rays" had been known for some time before Thomson. They were first observed as experiments in gas discharge tubes started to exploit better and better vacuums (the early experiments observed the varying forms of discharge in low pressure gases; cathode rays only become significant when there is very little gas left in the tubes).
Anode and cathode in electrolysis - Chemistry Stack Exchange
2020年9月22日 · Chemically stable in water and in oxydizing environment of the anode / reducing environment of the cathode. Most metals are OK being cathode in electrolysis as they fulfill both conditions. Well, sodium and friends are not good - it is not stable in water in the first place. Some non-metal substances are also acceptable - e.g. graphite.