01 Ethene Gas
Summary
TLDRThis educational video demonstrates the laboratory preparation of ethylene gas from ethanol. It outlines the necessary equipment, including a test tube with a sidearm and a Bunsen burner, and the use of aluminum oxide as a dehydrating agent. The script details the steps for heating, collecting ethylene, and conducting tests for unsaturation using acidified potassium permanganate and bromine water. It also explains how to identify ethylene gas through its bright blue flame test and the presence of carbon dioxide, verified by the milkiness of lime water.
Takeaways
- 🔬 The experiment involves the preparation of ethylene gas (C2H4) from ethanol.
- 🌡️ The process requires heating ethanol in the presence of aluminum oxide as a catalyst.
- 🧪 A test tube with a sidearm and a Bunsen burner are used for the reaction setup.
- 🔥 The aluminum oxide is heated to initiate the dehydration of ethanol to produce ethylene.
- 💧 Glass jars are used to collect the ethylene gas, and glass wool is used to support the ethanol inside the test tube.
- 🌬️ The initial bubbles produced are displaced air, not ethylene, which is collected once the air is displaced.
- 🧪 Lime water and acidified potassium permanganate are used to test for the presence of ethylene, indicating unsaturation by decolorization.
- 🔥 Ethylene gas burns with a bright blue flame, which is a characteristic test for its presence.
- 🌿 Bromine water is used to test for unsaturation, where ethylene gas decolorizes the bromine water due to the addition reaction across the double bond.
- ⚗️ The byproduct of the reaction is carbon dioxide, which is tested using lime water turning milky.
Q & A
What is the main reaction described in the script?
-The main reaction described in the script is the preparation of ethene gas (C2H4) from ethanol (C2H5OH) through a dehydration process.
What is the role of ethanol in this reaction?
-Ethanol serves as the starting material, which is dehydrated to form ethene gas and water.
What is the purpose of aluminum oxide in this reaction?
-Aluminum oxide acts as a dehydrating catalyst to facilitate the removal of water from ethanol, leading to the formation of ethene.
Why is a tight-fitting Bunsen burner used in the reaction setup?
-A tight-fitting Bunsen burner is used to ensure efficient heating of the reaction mixture and to prevent the escape of ethene gas.
What is the significance of glass wool in the reaction setup?
-Glass wool is used to support the ethanol and prevent it from splashing out of the test tube during heating.
How is the presence of ethene gas confirmed in the script?
-The presence of ethene gas is confirmed by testing for unsaturation using acidified potassium permanganate and bromine water, both of which should decolorize in the presence of ethene.
What is the purpose of the glass trough in the reaction setup?
-The glass trough is used to collect ethene gas during the reaction, preventing it from escaping into the atmosphere.
Why is it important to remove the rubber tubing before moving the glass jar in the script?
-Removing the rubber tubing before moving the glass jar prevents the formation of a vacuum inside the test tube, which could cause the test tube to shatter due to the contraction of gases upon cooling.
What is the test for the presence of carbon dioxide in the reaction?
-The presence of carbon dioxide is tested by adding lime water to the reaction container; if carbon dioxide is present, the lime water will turn milky.
How is the ethene gas identified in the script?
-Ethene gas is identified by its characteristic bright blue flame in a flame test.
Outlines
🔬 Preparing Ethane Gas from Ethanol
The video script describes a chemistry experiment to prepare ethane gas from ethanol. Ethanol, a two-carbon compound with hydroxyl groups, is dehydrated to form ethane and water. The setup includes a test tube with a sidearm, a Bunsen burner for heating, and a glass trough for gas collection. The reaction requires ethanol, aluminum oxide as a catalyst, and glass wool to support the ethanol. Indicators like lime water, acidified potassium permanganate, and bromine water are used to test for the presence of ethane gas, which is an unsaturated compound. The process involves heating the mixture to initiate the reaction and collecting the ethane gas in glass jars. The script also emphasizes safety measures, such as removing rubber tubing before moving the test tube to prevent shattering due to vacuum formation.
🧪 Testing for Unsaturation and Carbon Dioxide
This paragraph details the testing procedures to confirm the production of ethane gas and the presence of carbon dioxide as a byproduct. The tests for unsaturation include bubbling the collected gas through acidified potassium permanganate and bromine water, which should decolorize if ethane is present, indicating its unsaturated nature. The script also describes a flame test for ethane, where the gas burns with a bright blue flame, characteristic of ethane. Lastly, to verify carbon dioxide production, lime water is added to the container, which turns milky in the presence of CO2, confirming its presence. The script concludes with a step to decant the milky lime water into a test tube, visually demonstrating the presence of carbon dioxide.
Mindmap
Keywords
💡Ethanol
💡Ethylene
💡Dehydration
💡Aluminum Oxide
💡Bunsen Burner
💡Unsaturated Compound
💡Acidified Potassium Permanganate
💡Bromine Water
💡Lime Water
💡Flame Test
Highlights
Preparation of ethylene gas from ethanol is described.
Ethanol's molecular structure with two carbons and an O-H bond is explained.
The reaction produces ethylene and water, maintaining molecular balance.
A test tube with a sidearm and a tight-fitting ball is used for the reaction apparatus.
Aluminium oxide is used as a dehydrating agent for the ethanol.
A Bunsen burner is used for heating the reaction mixture.
Glass jars are used for collecting ethylene gas.
Lime water, acidified potassium permanganate, and bromine water are used to test for unsaturation.
Glass wool is used to support the ethanol inside the test tube.
Ethanol is introduced into the test tube using a squeezy bottle.
Aluminium oxide is added to the test tube to create a larger surface area for the reaction.
The rubber tubing is removed to prevent melting during heating.
The reaction is initiated by heating the aluminium oxide, not the ethanol.
Displaced air is removed before collecting ethylene gas.
Ethylene gas is collected in glass jars and tested for unsaturation.
Acidified potassium permanganate decolorizes, indicating the presence of unsaturated gas.
Bromine water decolorizes when bubbled with ethylene gas, confirming unsaturation.
Ethylene gas burns with a bright blue flame, a characteristic test for its presence.
Lime water turns milky in the presence of carbon dioxide, indicating a byproduct of the reaction.
Transcripts
[Music]
the reaction we're going to do now is
the preparation of 18 gas this involves
having ethanol ethanol consists of two
carbons with an old-age bond here all
the whites represent hydrogen's I was
going to turn each ethanol into 18
that's the structure of eighteen and
water what that reaction then involves
if you look on the right hand side
you've got the same molecules as on the
left hand side so we're going to get our
ethanol remove the water molecule from
that I left behind with an ET molecule
eighteen because as a double bond is an
unsaturated compound the reaction
apparatus for this is a test tube with a
sidearm a very tight fitting ball it's
imperative a very tight fitting form in
this particular practical and then a
Bunsen burner for heating aluminium
oxide and here I've got my glass trough
to collect 18 gas and I'd want to
collect the eating gas in these glass
jars here the chemicals required for
this practical are ethanol which will be
dehydrating so I put I've taken the
ethanol here and put it into a squeezy
bottle we will be using aluminium oxide
to dehydrate the alcohol so here's a
Lamia oxide and you can see from the
petri dish in front of us
it's a white powder non-transition metal
element then the test to see whether we
have it in gas produced are using lime
water acidified potassium permanganate
and bromine water we also need some
glass wool to support the ethanol before
we start the dehydration reaction the
first thing in this particle is pulling
the ethanol into the test tube so here
are my adult in my squeezy bottle are
nothing to stoichiometrically
just adding about 25% for the volume of
the test you pull that now
my ethanol's now be introduced now
ethanol is now on the inside of this
test tube so what I want to do is take
make sure that ethanol is removed by
putting in my glass wool that's gonna
take the ethanol down off the side of
the tube then using your spatula let's
drive inside the test tube
ice of course the alcohol might you now
I want to add my dehydrating catalyst my
aluminium oxide so have my aluminium
oxide my white powder allomere oxide
it's a very finely divided powder I put
my annum innum oxide on the inside of
the test tube now as much as possible
because the more surface area available
better the catalytic reaction that
happens so again I'm not doing this
stoichiometrically I'm just adding in
minim oxide no to create a larger
surface area as possible you may notice
I removed the rubber from the clamp
because this test shoot is very hot so
in order to stop the rover from melting
I've actually taken it away
he's a very tight bomb in order to stop
the e-team gas from escaping so all of
my tests you ain't going to get that
bonus tight as possible the normal
reaction is ready to go next part of
this reaction is the heating of the
Delirium oxide to start dehydrating the
ethanol into e-team so I have my glass
jar ready to receive the gas both the
first few bubbles of gas that are
produced are going to be the displaced
air is in the test tube and in the
rubber tubing but first of all have to
be displaced once i've displaced all
that air i can then start collecting my
eating gas and i have my my trough on my
glass y'all ready we're catching up take
your gas
so next procedure is to light the Bunsen
burner
now we've got our Bunsen burner lit
we're gonna start heating the other
medium oxide notice I'm eating the
aluminum oxide and not the ethanol and
we can already see bubbles of gas come
out the tube that is not product that is
displaced air so let that happen
rope while I mostly decided we've got
the volume of gas start to collect our
gas at this stage we will have 18 gas
coming out of the tube so put into my
beehive and then put my glass jar on top
of the Beehive and we can see bubbles of
gas oriented glass jar that's 18 gas is
now being collected oil a glass jar is
filling of eating gas you prepared to
test for the unsaturation to test for
unsaturation are bobbing the solution
true roaming water we want to fill to
test ships full of Brawley water one
connect us to control we can test and
likewise I have pacified potassium
permanganate
I'll fill two trips again one the test
ship wanted to experiment on and one is
to control will allow for the brought
the eating gas to the acidified
potassium magnet and if we have an on
such a gas you should notice the
attachment Magnus is decolorizing
you see the gas bubbles bubbling true
and then when you compare that to
control we can see decolorization
has occurred therefore proving it's an
unsaturated compound second test for D
saturation is the decolorization
of bromine water so here I have my
solution of bromine water and I'm going
to bubble eating gas through the bromine
water and the bromine is adding across
double bond so decolorizing the solution
so if we compare that to a test tube to
the control we can see the color ization
has occurred so proving we produce an
unsaturated gas i've now collected the
eating gas in the glass jar I can move
the glass jar and put the coverslip
myelinated and we're going to be doing
the flame tests to see that we've got 18
gas produced it's very important at this
stage to remove the rubber tubing before
you move the roof on some burner if we
remove the Bunsen burner first what
happens is the gasses inside the test
you contract so causing a vacuum inside
the apparatus drawing the water from the
rubber tubing in the test tube and it
has you can shatter so the test for
eating gas is a burns in a bright new
messin flame so always light your
lighter before you remove the cover slip
and then white gas i will notice burning
with a bright blue messin flame the
bipod out of the reaction would be
carbon dioxide in order to check the
presence of carbon dioxide i'm going to
add some lime water into the container
answers carbon dioxide present the lime
water will turn milky shake this up
so we should notice how the lime water
is turning milky and just a short that
milkiness i will decant that into a test
tube so if you see the milky color of
the lime water so proving the presence
of carbon dioxide
Weitere ähnliche Videos ansehen
5.0 / 5 (0 votes)