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This is a Clilstore unit. You can link all words to dictionaries.

Electrochemistry

CLIL Unit. 2018

  

Lesson 1. General Concepts

1.1 What can YOU tell me about energy?

  1. What sources of energy do you know?
  2. Are they renewable?
  3. What is the Greenhouse Effect? Do you know its causes and consequences?
  4. What kind of motor use the vast majority of cars nowadays?

After answer these questions we are going to watch an interesting video about "Electric Cars & Warming Emissions" 

 

 

[Music]
00:00
here's a question how much cleaner are
00:03
battery electric cars compared to
00:05
gasoline-powered cars to find out the
00:08
Union of Concerned Scientists studied
00:10
the total global warming emissions of
00:11
each vehicle throughout every stage of
00:13
its life from manufacturing to driving
00:17
to disposal and there's a big difference
00:20
both cars start out on the assembly line
00:23
with similar parts made of raw materials
00:26
like steel and aluminum for a gasoline
00:28
car this manufacturing and assembling
00:31
stage generates about seven tons of
00:33
emissions battery electric cars
00:35
meanwhile are powered by you guessed it
00:38
a large battery this requires more
00:41
energy and materials to produce for an
00:43
84 mile range battery electric car
00:46
bringing its emissions tally up to
00:48
roughly eight tons but what happens when
00:51
they hit the road gas-powered cars
00:54
produce pollution with every gallon of
00:55
gas they burn with even more emissions
00:58
coming from extracting refining and
01:01
transporting the fuel to gas stations
01:04
electric cars on the other hand run on
01:06
electricity which can be much cleaner
01:09
than gasoline depending on how the
01:11
electricity is made two-thirds of
01:14
Americans live in regions where charging
01:17
an electric car produces fewer global
01:19
warming emissions and driving even a 50
01:21
mile per gallon gasoline car by the end
01:25
of their lives the average gas car will
01:28
rack up 57 tons of global warming
01:30
emissions compared to 28 tons for a
01:33
battery electric car disposing and
01:36
recycling each car adds less than one
01:38
ton of emissions and remember that
01:40
electric car battery it can be recycled
01:43
or reused in the final tally an 84 mile
01:48
range battery electric car cuts global
01:50
warming emissions by more than 50
01:52
percent compared with a similar sized
01:54
gas powered car making up for the
01:56
batteries manufacturing emissions within
01:58
one year of driving and as the country
02:01
adds more and more renewable sources of
02:03
electricity driving electric will get
02:06
even better so there you have it
02:09
straight from the engineers at the Union
02:11
of Concerned Scientists
02:13
electric cars clean and getting cleaner

1.2 Oxidation and Reduction Review

 Oxidation-reduction reactions, also known as redox reactions, consist on any chemical reaction in which the oxidation number of chemical species changes. It means that involves a transfer of electrons between two species.

An interesting example of redox reactions is the combustion reaction that is studied in the following video and serve us to review basic concepts about oxidation and reduction.

 

After watching this video you can practice trying to calculate the oxidation number of different molecules in the solved exercise that is attached to the link buttons "Oxidation Number".

1.3 What is Electrochemistry?

The branch of chemistry that studies the relations between electrical and chemical phenomena.

Watch the video "Introduction to Electrochemistry" from Tyler Dewitt and do the "Electrochemistry Quiz" to review your knowledge.

00:00
this video is an introduction to
00:02
electrochemistry
00:03
so what's electrochemistry well you
00:05
might have guessed it has something to
00:07
do with electricity and chemistry and
00:10
that's exactly right
00:11
specifically electrochemistry is about
00:14
the relationship between chemical
00:17
reactions and electricity when we're
00:20
studying electrochemistry they're
00:21
basically two main ways that chemical
00:24
reactions and electricity interact
00:27
here's the first one certain chemical
00:31
reactions can create electricity okay so
00:35
like that's what's going on in a battery
00:37
they're chemicals inside the battery
00:39
they react together making a chemical
00:40
reaction and that chemical reaction
00:43
creates electricity okay so that's the
00:45
first way that these two things interact
00:47
with each other the second is that
00:50
electricity can make certain chemical
00:54
reactions happen that wouldn't happen
00:56
otherwise we'll look at examples of both
00:59
of these situations so if we're going to
01:01
be talking about chemical reactions and
01:02
electricity here let's just take a
01:04
minute to explain what these two things
01:06
are so we can know we're dealing with
01:08
first off electricity what is it well in
01:12
really simple terms
01:14
electricity is just movement of
01:17
electrons I got a bunch of electrons in
01:19
this diagram they're moving in this
01:21
direction so have electricity often when
01:24
we talk about electricity we're talking
01:26
about movement of electrons through
01:28
something so maybe it's through a wire
01:30
or through a light bulb or through a
01:32
battery or something like that but if
01:34
you got electrons moving you've got
01:36
electricity so if electricity is about
01:40
moving electrons that means the chemical
01:43
reactions that we're going to be talking
01:45
about are also going to involve movement
01:48
of electrons and that means that these
01:50
chemical reactions that we're going to
01:52
be discussing will tend to be oxidation
01:55
reduction reactions because these are
01:58
chemical reactions where electrons move
02:01
between atoms okay so here's how these
02:05
two scenarios come into play we can use
02:08
electrons moving between atoms in an
02:12
oxidation reduction
02:13
action to make electricity the electrons
02:16
are moving so there's our electricity
02:18
and then for this situation we can use
02:21
electricity to force electrons to move
02:26
between atoms to make oxidation
02:29
reduction reactions happen let's look at
02:32
how that would work so here I've got an
02:34
oxidation reduction reaction where
02:36
electrons are moving from A to B how can
02:39
I use this to create electricity like a
02:42
long wire well what we could do is we
02:45
could separate a and B right we know
02:50
that electrons want to move from A to B
02:52
so if we separate them with a wire then
02:55
that means that the electrons moving
02:57
between these atoms will have to travel
02:59
through the wire being moving through
03:02
that wire and bam we've got electricity
03:05
okay now let's look at this example okay
03:08
let's imagine we have another oxidation
03:10
reduction reaction electrons
03:13
transferring from C to D but imagine
03:17
this doesn't normally happen because C
03:19
doesn't want to give up electrons and D
03:21
doesn't want to gain okay here's where
03:24
we can use electricity okay we can take
03:27
the electrical energy from a battery and
03:30
use that to oh to pull the electron from
03:34
from C here and to push them to D okay
03:39
so even if this reaction the movement of
03:41
electrons doesn't normally happen we can
03:44
use electricity we can use the
03:45
electrical energy of this battery to
03:48
pull and push the electrons to make this
03:51
reaction happen okay so this is kind of
03:54
a broad big-picture overview of
03:57
electrochemistry now I want to show you
03:59
two examples of these situations one
04:03
where we're using a chemical reaction to
04:05
create electricity and one where we're
04:07
using electricity to make a chemical
04:09
reaction happen so here's how chemical
04:12
reactions can create electricity and to
04:15
do this to make electricity using
04:17
chemical reactions we often use a device
04:19
called a galvanic or voltaic cell I've
04:23
drawn one right here the version that
04:25
I've drawn uses
04:26
zinc and copper metals so let's take a
04:29
look at the chemical reaction that's
04:31
happening in this galvanic cell that is
04:33
what's creating electricity so here's a
04:36
chemical reaction we said that that
04:37
galvanic cell use zinc and copper so if
04:41
you take a neutral zinc atom and put it
04:44
near a copper 2 plus ion electrons
04:48
naturally move from the zinc atom to the
04:52
copper and so what happens there is the
04:55
zinc takes on a two plus charge because
04:58
it loses two electrons and the copper
05:01
becomes neutral because it gained two
05:04
electrons so why does this happen
05:07
well that's because there's kind of a
05:08
tug-of-war between these ABS Cu 2 plus
05:13
has a strong pull for electrons and zinc
05:17
Zn has a weaker pull for electrons and
05:21
that's why the electrons move we can
05:24
describe how they move in terms of
05:26
oxidation and reduction zinc over here
05:29
is losing electrons so it is oxidized Cu
05:34
2 plus is gaining electrons so it's
05:38
reduced now the most important thing
05:41
about this process is that it happens on
05:44
its own all you got to do is put neutral
05:48
zinc near copper two-plus and the
05:51
electrons just naturally move it happens
05:54
on its own this is a process that we can
05:57
call spontaneous it's spontaneous it
05:59
just happens on its own now a really
06:01
common question that's a great question
06:03
is people say okay yeah but like how do
06:06
you actually know that the electrons are
06:09
going to move from zinc to copper how do
06:11
you know that copper has a stronger pull
06:13
for electrons well you can look it up
06:16
there is this chart that we'll be using
06:18
a lot in electrochemistry it's called
06:20
the standard reduction potentials and it
06:23
lists elements and compounds in terms of
06:27
how strongly they want to pull electrons
06:29
so the higher you go up here the more
06:32
these elements want to pull electrons
06:34
towards them so we got copper two-plus
06:37
up here and we got zinc
06:39
down here so where this chart works is
06:42
if copper is up here if it's above zinc
06:46
down here then copper is going to be
06:48
stealing electrons from zinc copper is
06:51
going to have a stronger pull so that's
06:52
how we know that copper is normally
06:55
going to be pulling electrons from zinc
06:58
and that this reaction is just going to
06:59
happen on its own so this reaction as we
07:04
said is what's going on in a galvanic
07:07
cell so let's see how we can use this
07:09
galvanic cell to create electricity from
07:13
this reaction okay well we send zinc is
07:18
going to be giving electrons to Cu 2
07:20
plus but when these atoms just give
07:24
electrons to each other just like that
07:26
it doesn't really create electricity
07:28
that's very useful for us but if we can
07:32
separate the zinc and the copper
07:35
two-plus then we can make the electrons
07:38
travel through a wire in order for them
07:42
to move and that is exactly what we do
07:45
in this galvanic cell okay check this
07:48
out we got zinc here in this container
07:51
and then we got a whole bunch of Cu 2
07:53
plus in this container
07:55
there's also Zn 2 plus here but it's not
07:57
not really that important so what
07:59
happens is the electrons want to get
08:01
from this zinc to this Cu 2 plus but in
08:04
order to do that they've got to go
08:07
through this wire so this is the path
08:10
that the electrons take they're moving
08:13
through this wire to get from the Zn to
08:16
the Cu 2 plus and check it out they're
08:18
moving along this wire which means that
08:22
they are creating electricity they go
08:25
into this piece of copper and then they
08:27
move here wanting to get to the Cu 2
08:30
plus so we've got electrons moving in
08:33
this direction and as I showed earlier
08:35
we can even take a light bulb or
08:38
something and put it between here and
08:40
the light bulb will light up because
08:42
there's electricity moving through this
08:44
wire as the electrons naturally
08:48
spontaneously move from the zinc
08:51
to the copper all right now in
08:56
electrochemistry we often want to
08:58
describe what is happening in a device
09:00
like this using oxidation and reduction
09:04
we want to be able to talk about the
09:06
different parts of a galvanic or voltaic
09:09
cell and say what's happening to them
09:12
with electrons so here just a couple
09:14
words that we'll need to know these two
09:16
pieces of metal the zinc and the copper
09:19
are called electrodes the electrons are
09:24
going into the electrode and coming out
09:26
of the electrode and now we can name
09:29
these electrodes based on whether
09:31
oxidation or reduction is happening
09:34
there okay here are two words we use all
09:36
the time in electrochemistry the anode
09:40
is where oxidation happens and the
09:43
cathode is where reduction happens so
09:46
let's look at what's going on here okay
09:47
we got zinc what's going on with a zinc
09:50
well we know that zinc is losing
09:52
electrons it's being oxidized because
09:54
the electrons are moving out of the zinc
09:56
to get over here to the Cu 2 plus so the
09:59
zinc is losing electrons it's oxidized
10:01
which means that the piece of zinc here
10:04
is the anode the place where oxidation
10:07
is happening over here the copper the
10:11
copper is where electrons are getting
10:14
added to the Cu 2 plus so the piece of
10:19
copper as an electrode is the cathode
10:22
it's where reduction it's where gain of
10:25
electrons is happening so the zinc is
10:28
the anode because it's a site of
10:29
oxidation the piece of copper is the
10:32
cathode because it's the site of
10:34
reduction so this is how a galvanic cell
10:37
uses a spontaneous chemical reaction
10:40
that happens on its own to create
10:43
electricity
10:44
okay so anode cathode how are you going
10:48
to remember them well this is a really
10:49
easy mnemonic a way to remember okay
10:51
it's kind of like thinking about two
10:53
animals okay an ox red cat just remember
10:59
that right now okay it stands for anode
11:01
is the site of oxidation and
11:04
Ochs red cat stands for reduction
11:09
happens at the cathode an ox red cat
11:13
learn it right at the top of your tests
11:15
you'll never mix these things up again
11:17
now let's look at how we can use
11:20
electricity to make certain chemical
11:22
reactions happen that wouldn't happen
11:25
otherwise using electricity to make
11:27
chemical reactions happen is a process
11:30
called electrolysis we do electrolysis
11:33
in a device called an electrolytic cell
11:36
I got a diagram of one of these here and
11:37
in our example we're going to see how we
11:40
can use electrolysis in an electrolytic
11:43
cell to take water and split it apart
11:47
into hydrogen gas and oxygen gas so just
11:51
like the reaction we saw earlier with
11:52
zinc and copper
11:54
this is also an oxidation reduction
11:57
reaction we got electrons moving here to
12:00
understand how they move we got to take
12:02
a look at the oxidation numbers for the
12:04
different elements here hydrogen's
12:06
oxidation number is going down which
12:09
means that it is gaining electrons it is
12:12
a reduced oxygens oxidation number is
12:15
going up which means that it is losing
12:17
electrons it is getting oxidized so we
12:20
can kind of sum up what's going on here
12:22
with a diagram like this electrons are
12:24
moving from oxygen which is losing them
12:26
to hydrogen which is gaining but this is
12:29
a problem okay it's a problem because it
12:33
goes against what oxygen and hydrogen
12:36
normally do with their electrons okay
12:40
oxygen has a stronger pull for electrons
12:44
and hydrogen has a weaker pull for
12:49
electrons so if it could oxygen would
12:53
want to take electrons from hydrogen and
12:56
hydrogen Cana would be willing to lose
12:57
them but for this reaction to happen
13:00
we're asking that the opposite take
13:04
place okay oxygen is usually stronger
13:07
but we're asking it to give up electrons
13:09
hydrogen is usually weaker it usually
13:12
losing electrons but here we're asking
13:14
for hydrogen
13:15
to gain electrons and we can look again
13:18
at this list of standard reduction
13:20
potentials just to see who's stronger
13:22
and who's weak all right oxygen is up
13:25
here the further up you are the stronger
13:28
Pole you have four electrons hydrogen is
13:30
all the way down here so you can see
13:32
that oxygen really wants to take
13:34
electrons from hydrogen but instead
13:37
we're asking AXA j'en to give electrons
13:40
to hydrogen okay so based on that
13:43
information this is a reaction that
13:46
doesn't happen on its own because oxygen
13:49
doesn't want to give up these electrons
13:51
so we can say that it is not spontaneous
13:54
it's not going to happen on its own
13:56
we're going to have to use electricity
13:58
to make it happen and it turns out that
14:02
a battery the electrical energy from a
14:05
battery can pull the electrons from
14:08
oxygen and push them to hydrogen it can
14:12
force this reaction to happen here's how
14:15
so we can make this process happen by
14:17
using an electrolytic cell this is some
14:20
water here that we want to break down
14:21
we've got these electrodes and the
14:23
electrodes are connected to a battery
14:25
okay so normally oxygen has a stronger
14:28
pull for electrons but we can use the
14:31
strength of the battery to pull
14:34
electrons away from oxygen okay here
14:38
hydrogen would normally give up
14:40
electrons but we can use the battery to
14:43
push electrons to hydrogen in terms of
14:47
oxidation and reduction this means that
14:49
oxygen is losing electrons so it is
14:52
getting oxidized hydrogen is gaining
14:56
electrons so it is getting reduced these
14:59
electrons are getting pushed to it from
15:01
the battery okay so what about anodes
15:04
and cathodes remember an ox Redcat anode
15:08
is where oxidation happens so over here
15:11
is the anode the site of oxidation where
15:14
oxygen is losing electrons and over here
15:17
is the cathode where hydrogen is getting
15:20
reduced so this is how electrolysis
15:23
happens we force the electrons to leave
15:26
oxygen and we
15:28
push them into hydrogen making this
15:30
process happen using a device like this
15:32
called an electrolytic cell so that's an
15:35
introduction to electrochemistry we
15:37
looked at two ways chemical reactions
15:40
and electricity interact certain
15:43
chemical reactions does it happen on
15:44
their own those that are spontaneous can
15:47
create electricity in order for that to
15:50
happen we separate the two things that
15:53
electrons are moving between we put a
15:55
wire in between them so the electrons
15:58
will move through the wire electricity
16:02
can make certain chemical reactions
16:04
happen that wouldn't happen otherwise if
16:06
a certain atom doesn't want to give up
16:09
electrons or another atom doesn't want
16:11
to gain them we can use the electrical
16:13
energy from a battery to pull electrons
16:16
and to push them forcing oxidation
16:19
reduction reactions like this to happen
16:21
we looked at how galvanic or voltaic
16:23
cells use processes like these and we
16:27
talked about the electrolysis process of
16:29
breaking down h2o water into h2 and o2
16:33
so that's a good example of this

Lesson 2. Galvanic vs Electrolytic Cells

2.1 Galvanic or Voltaic Cells

Electrochemical cell where spontaneous redox reactions are used to produce electricity. It consists of two half-cells composed of an electrode (M) in a solution containing the Mn+ ions. These two half-cells are linked by a wire that goes from one electrode to the other. It is also needed what is known as salt bridge.

Watch the video and complete the first exercise of the Lesson 2 called "Galvanic Cells".

 

2.2 Nerst Equation

This equation enables to determine the cell potential under non-standard conditions. It relates the equillibrium cell potential to its concentration across the membrane. So, it permits to calculate the voltage of an electrochemical cell or on the other hand to find the concentration of one of the components of the cell.

Watch the video and solve the problems attached under the name "Nerst Equation".

2.3 Electrolysis of water

It is the process of using electricity to split water into hydrogen and oxygen. So, it is a promising option for hydrogen production from renewable resources. It takes place in an unit called electrolyzer which can size from small to appliance-size.

Watch the video and complete the second exercise of the Lesson 2 called "Electrolysis of water".

 

00:00
welcome to the side guys on today's
00:01
episode electrolysis
00:17
hi I'm Adam and I'm Ryan for the side
00:20
guys and today we're going to be showing
00:21
you electrolysis breaking the bonds of
00:23
oppression you mean chemistry yeah that
00:27
works too what we're going to be doing
00:28
today is adding energy in the form of
00:30
electricity into a compound to break its
00:32
chemical bonds we're turning it into its
00:34
base components this is called
00:36
electrolysis the equipment you need for
00:38
this experiment is a 9-volt battery a
00:40
couple of spoons to act as leads to
00:43
conduct the electricity from the battery
00:44
into our solution a Pyrex speaker this
00:47
is volumetric alternatively you can use
00:50
another Pyrex like product from your
00:52
kitchen store we recommend something
00:54
with a little bit of heat resistant and
00:55
something separate from what you cook
00:57
with just so you're not going to get
00:58
cross-contamination next we'll show you
01:00
the ingredients you're going to need
01:04
because water has a really low
01:06
conductivity first ingredient we're
01:08
going to have to get is salt to increase
01:11
the conductivity so that a 9-volt
01:12
battery will cause the reaction we need
01:14
we're going to recommend you use kosher
01:16
salt because it's only NaCl secondly the
01:22
solution at the end of this will be
01:24
basic so we're going to have to
01:26
neutralize it for disposal we're going
01:28
to recommend to use vinegar
01:31
the last ingredient were going to need
01:33
is distilled water we're using distilled
01:35
water rather than tap water because that
01:37
way we know exactly what's in it and we
01:39
won't have any impurities messing with
01:41
our experiment it's ABS is all about
01:43
controlling your parameters now before
01:45
we get started you're going to have to
01:46
Don your safety equipment the safety
01:48
equipment we need for this experiment a
01:50
thick rubber gloves pair of goggles and
01:52
an apron or lab coat even though we're
01:55
only dealing with saltwater in this
01:57
experiment the reaction can create lye
01:59
which is an extreme base so to protect
02:02
against spills and splashes wear your
02:05
gloves and goggles the first step in
02:08
setting up this experiment is to mix
02:10
together the saltwater solution the
02:12
ideal ratio of saltwater for
02:14
electrolysis is 10% salt in 90% water
02:18
this is best calculated by weight what
02:20
this means is for every 90 grams of
02:23
water you need to mix in 10 grams of
02:25
salt we've measured out 540 grams of
02:27
water
02:28
once you've measured your water pour it
02:30
into your glass container next measure
02:33
an add your salt into the container
02:34
we've measured out 60 grams of salt this
02:37
gives our solution a total weight of 600
02:39
grams now stir the solution until as
02:42
much of the salt as possible has been
02:44
dissolved into the water
02:45
this step may take a few minutes the
02:48
next step is best done with a partner
02:50
take your spoons or your leads and
02:53
submerge them into the water make sure
02:55
they're not touching next press the
02:56
battery terminals against the ends of
02:58
the spoons make sure that only one spoon
03:00
is touching each terminal as soon as the
03:03
batteries touch the spoons you should
03:04
see bubbles forming on the spoons these
03:07
bubbles are filled with hydrogen and
03:08
chlorine gases if the spoons touch you
03:12
will create a short-circuit and the
03:14
reaction will stop if you separate the
03:16
spoons and the batteries still attached
03:18
the reaction should continue it is
03:20
important to note that chlorine gas is
03:23
toxic if inhaled and lye a corrosive
03:25
alkaline can burn your skin the amounts
03:28
produced in this experiment are very
03:30
small even so you should always do this
03:33
experiment in a well-ventilated space or
03:35
outside while wearing eye protection and
03:38
heavy rubber gloves you'll notice the
03:41
longer our reaction continues the water
03:43
will turn from a clear colour to yellow
03:46
and then to green and brown let's look
03:50
at this reaction a little closer
03:52
one eight ounce cup of water contains in
03:55
the neighborhood of seven point nine one
03:57
times ten to the power of 24 molecules
04:00
of water that comes out to be around
04:02
this many molecules of h2o and every cup
04:04
this puts into perspective how very
04:07
small molecules are now water is a poor
04:10
conductor of electricity this is where
04:12
salt comes in salt is a type of
04:14
substance called an electrolyte which
04:17
when dissolved in water increases the
04:19
conductivity of the water and makes it
04:21
easier for electricity to move through
04:23
it now our solution has tons of water
04:25
sodium and chlorine floating about when
04:28
we add energy in the form of electricity
04:30
to our now conductive solution it causes
04:32
the bonds and the water molecules to
04:34
break all of these ions are now floating
04:36
in our solution which leaves them free
04:38
to create new bonds sodium joins up with
04:40
oxygen and hydrogen to create sodium
04:42
hydroxide or lye
04:44
this leaves chlorine and hydrogen which
04:47
bond with like ions forming chlorine and
04:49
hydrogen gases and they flowed out of
04:51
our solution into the air the bubbles
04:53
forming on the spoons contain these
04:55
gases if we look at the formula in this
04:58
reaction it looks like this as you can
05:00
see in these reactions nothing is
05:02
created or lost everything is used the
05:04
things we started out with are the same
05:06
as what we finished with just jumbled
05:08
around a little bit based on how they
05:10
like to join together that's basic
05:12
chemistry the change in color in our
05:13
reaction is because we are using metal
05:15
spoons and they are causing the creation
05:17
of a precipitate or solid oxide in our
05:20
container this is an unknown variable in
05:22
our experiment because we don't know
05:24
what the spoons are made of in
05:25
commercial labs they use graphite leads
05:28
because they don't cause the creation of
05:30
an oxide if we would use graphite
05:32
pencils that were sharpened on both ends
05:34
and then touch the battery to them this
05:36
would eliminate the creation of the
05:38
oxide and remove the unknown variable
05:39
once you're done watching your
05:41
experiment disconnect the battery from
05:44
the end of the spoons then remove your
05:46
spoons from your liquid solution you can
05:49
wash these with soap and water so what
05:51
we've done is broken the bonds of your
05:53
hydrogen and oxygen in the water and
05:55
sodium and chlorine in the salt what was
05:58
produced is hydrogen and chlorine gases
06:00
which escape into the air
06:01
lye and an oxide which you can see as
06:04
precipitate
06:05
because lye is produced in this reaction
06:07
and lye is a very strong base we're
06:10
going to have to neutralize our solution
06:12
before we can properly dispose of it
06:14
this is where the vinegar comes in
06:16
vinegar is an acid pour vinegar into
06:19
your solution and it will bring the pH
06:22
down to a neutral level which is safe
06:24
for disposal turn your water on in your
06:26
sink and let it run for a few seconds
06:29
then pour your solution directly down
06:33
the drain of the sink wash your
06:35
container out and pour that as well down
06:37
the drain let your water run for a few
06:40
more seconds to make sure that our
06:42
entire solution is thoroughly washed
06:43
down the drain
06:44
so that's electrolysis if you have any
06:47
questions related to electrolysis or any
06:49
other science topic throw them in the
06:51
comments below and we'll try to answer
06:52
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06:53
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07:01
thanks for watching bye here at SCI guys
07:05
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07:07
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07:09
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07:11
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Clilstore Oxidation NumberElectrochemistry QuizLesson 2Nerst EquationFinal Presentation

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