English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

In our textbook it says "By convention, current flows from the positive electrode of a cell to the negative electrode. Actually, it is the electrons that are flowing. The flow of currnet and electrons are opposite in direction." I know that electrons in the external circuit flow from the negative terminal to the positive terminal, but the sentence in our textbook seems quite confusing. Can someone please kindly explain this? Thanks!

2007-03-10 22:52:06 · 5 answers · asked by Anonymous in Science & Mathematics Chemistry

5 answers

This is an age-old conflict between physics and chemistry. Chemists got it right more than 100 years ago, but physicists still try to spare their blushes by pretending that some sort of current is flowing from positive to negative in the wires of the external circuit. It would me much simpler if everybody agreed that it is the electrons that move, their movement causes the current to flow in the external circuit, and they flow from the negative terminal to the postive terminal.

2007-03-10 22:58:39 · answer #1 · answered by Gervald F 7 · 0 1

This has everything to do with potential. The positive elctrode has more potential, the negative electrode has less, that is why current flows from a positive electrode (higher potential) to negative (lower potential). This is very much analogous to heat, which flows from a body at higher temperature to a body at lower temperature.

NB- potential is defined as the work done to bring a unit positive charge from infinity to a particular point. Potential difference is the difference in potential between the positive elctrode and the negative electrode in the external circuit. Current does not flow when there is no potential.

2007-03-11 07:01:42 · answer #2 · answered by chemistry nerd 2 · 0 1

There are 2 kinds of flow in an cicult +ve and -ve. Then Charge are formed on a electrode cicult one will have an electron and the other will have an electron hole, or valancy hole there the electron from that hole is on the ive electrode, Then current flows through the circults the electrons will move from the -ve to the -electrode while on the other hand electron holes will move from the +ve to the -ve.

2007-03-11 07:16:53 · answer #3 · answered by Mr Hex Vision 7 · 0 0

When the electricity was discovered, nobody knew that the electricity was due to motion of electrons or ions. Electron was discovered one century after electricity. So, they had to arbitrarily choice a sens of current. Unfortunately with the convention, the sense of the current was oppose to the sens of electrons 'flow and the electron bears a negative charge.

2007-03-11 07:03:27 · answer #4 · answered by maussy 7 · 0 0

Your are right of course, but the text is also correct. The key words are "by convection." The writer should have made that a little clearer, convection is a whole process and just sticking the words in doesn't give you enough information.

2007-03-11 06:59:54 · answer #5 · answered by Anonymous · 0 1

fedest.com, questions and answers