Edited Invalid date
19.10 Free Energy and Equilibrium: Relating -- Part 1
The house shown in this image is completely powered by batteries that are recharged with solar cells, eliminating the need to connect to the electrical grid.
This house could become commonplace with rapid advances in battery technology.
The power of the electrical charge is demonstrated by lightning.
In a battery, many of the same principles are at work.
Water droplets and ice particles collide in a thundercloud.
Positive and negative charges are created when the electrons are knocked off of the molecule.
On rising air currents, the positive charges accumulate on small ice crystals that travel to the top of the thundercloud.
The thundercloud is negatively charged by the wet slushy bottom.
Until a path can be formed between the bottom of the cloud and the top of the cloud, the resulting charge separation exists.
A channel of ionized air forms when the charge separation is great.
The charge separation is equalized by cloud-to-ground lightning.
The electrical charge is moving fast.
The earth underneath the cloud develops a positive charge if the thundercloud gets close to the ground.
Cloud-to-ground lightning occurs when a channel of ionized air forms between the ground and the cloud.
Cloud-to-ground lightning can be seen on the ground.
Many of the same principles that are used in lightning are used in batteries.
A battery has different affinities for electrons.
One end of the battery develops a positive charge while the other end develops a negative charge because the substances are separated.
A path through which charge can flow is what the charge separation is about.
A metal wire with an electrical load can be used.
electrons flow from the negative end of the battery to the positive end when the wire is connected The electrons can do electrical work when they flow through the electrical load.
You can now run your entire home from a bank of batteries, thanks to battery technology that has advanced dramatically in recent years.
It is possible to live off the traditional electrical grid with the help of these batteries.
The oxidation state of calcium increases from 0 to +2.
It is reduced because hydrogen decreases in oxidation state.
The overall equation is broken down into two half-reactions, one for oxidation and one for reduction.
We add the half-reactions together.
Reactions occurring in acidic and basic solution have slightly different steps.
The M20_TRO4371_05_SE_C20_896-945v 3.0.2.indd was reduced and oxidation occurred.
Adding H+ will balance H.
When a redox reaction occurs in basic solution, we balance the reaction in a similar manner, except that we add an additional step to neutralize any H+ with OH-.
An electrical current can be defined as electrons flowing through a wire or ion flowing through a solution.
The transfer of electrons from one substance to another has the potential to generate electrical current, as we discussed in Section 20.1.
The Cu2+ is transferred directly from the Zn.
The process of transferring two electrons to a copper ion in solution is more complicated, but we can imagine it on the atomic scale.
The zinc ion is dissolved in the solution.
The zinc is deposited as solid copper when the copper ion accepts two electrons.
We could force the electron transfer to occur through a wire connecting the two half-reactions, not directly from the zinc atom to the copper ion.
The electrons could be used to do electrical work.
electrons are transferred to the copper ion.
The zinc atoms are dissolved in the solution.
The copper is deposited on the electrode.
In Section 20.8 we discuss voltaic cells and electrolytic cells.
A second half-cell is formed by placing a strip of copper in a solution.
The zinc electrode becomes negatively flow to counteract charge build up.
The copper voltaic cell repels electrons by having one negatively charged electrode in it.
The Zn2+ equilibrium is affected by differences in ionization shifts to the right.
The Cu>Cu2+ equilibrium shifts to the left as electrons tendencies are central to understanding how a voltaic cell works.
The electrons form an electrical current that lights the bulb.
View flashcards and assignments made for the note
Getting your flashcards
Privacy & Terms