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  • Topic: Neutralization Reaction.

  • How to treat a bee sting?

  • Hey.

  • Hold On.

  • Don't go near that honeycomb.

  • Please listen to me.

  • It is quite dangerous.

  • Fine.

  • Go ahead.

  • See, I told you.

  • Ok.

  • Now, don't worry.

  • Put this baking soda solution on the bee stung area.

  • You got some relief, right?

  • Do you know why you got relief?

  • This happened because a neutralization reaction took place when we applied baking soda on the stung area.

  • The venom of a honey bee contains formic acid.

  • When it stings us, it injects that acid into our skin.

  • Formic acid causes immense pain and irritation.

  • However, when we apply baking soda solution, which is a mild base, on the stung area.

  • It neutralizes the formic acid and cancels its effect.

  • As a result, the sensation of pain and irritation decreases and we get some relief.

  • Such a reaction between an acid and a base is called neutralization.

  • In neutralization, both acidic and basic solutions neutralize the effect of each other and the nature of both acids and bases gets destroyed.

  • Hey, Wait.

  • What are you doing?

  • Don't tease that insect.

  • It is not a honey bee.

  • It looks similar to a honey bee but it is a bit longer.

  • It is called a wasp.

  • At least this time listen to me.

  • Ok.

  • Don't listen and bear the consequences.

  • Applying the baking soda is not going to help.

  • See, nothing is happening.

  • I will tell you what to do.

  • Pour this vinegar on the stung area, you will get some relief.

  • Why do you think the baking soda solution did not help in this case?

  • Earlier, in case of the honey bee, we learnt that its venom is acidic.

  • Hence, baking soda, being a basic solution helped to neutralize the effect

  • Now, in case of a wasp, the nature of its venom is basic.

  • When it stings us, it injects that venom into our skin.

  • This venom causes us pain and itching.

  • Now, baking soda is also a basic solution.

  • Hence, it will not provide any sort of relief.

  • However, when we pour vinegar, which is a mild acid, on the stung area, the acid, that is, vinegar and the base, that is, the wasp's venom get neutralized.

  • As a result, the sensation of pain and itching decreases and we feel better.

  • Topic: Rancidity.

  • Why is a bag of chips half full?

  • Looks like you don't believe me.

  • Open the bag.

  • See I told you.

  • The bag of chips is indeed half full.

  • Why is that so?

  • It is mainly because of a concept called rancidity.

  • When food becomes rancid, it develops an unpleasant smell and taste and it becomes unsafe for consumption.

  • Rancidity generally refers to a condition where the fats and oils present in food get oxidized, resulting in food spoilage.

  • Since the chips contain fats and oils, they are likely to get rancid.

  • Therefore, to prevent this, nitrogen gas is flushed into bags of chips by manufacturers.

  • But, why nitrogen?

  • Nitrogen does not react with fats and oils.

  • As a result, rancidity does not take place.

  • Moreover, a gas in the bag serves as a cushioning agent and prevents the chips from crumbling.

  • That is why the bag of chips is only filled till half.

  • Topic: Acid Base Indicators.

  • Why does a turmeric stain turn red?

  • No.

  • You got a stain on the shirt.

  • I know what you are thinking.

  • No, there is no point.

  • None of the two bottles are of any use.

  • Listen to me.

  • Don't wash the stain with the soapy solution.

  • The stain will turn red.

  • See, I told you.

  • Do you know why this happened?

  • This happened because the food which fell on the cloth had turmeric in it.

  • The color of turmeric is yellow.

  • It is a natural indicator which tells us whether a substance is an acid or a base.

  • Now, let us get back to those two bottles.

  • One contained lemon juice while one contained a soapy solution.

  • When we pour the lemon juice on the turmeric powder, we see that the color of turmeric powder is still yellow.

  • This is because lemon juice is an acid.

  • Turmeric does not change its color when it comes in contact with an acid, indicating that the lemon juice is an acid.

  • However, when we pour the soapy solution on the turmeric powder.

  • We see that the color of turmeric powder turns red.

  • This is because soap is a base.

  • When turmeric comes in contact with a base, it changes its color from yellow to red, indicating that the soapy solution is a base.

  • That is why a turmeric stain turns red when it comes in contact with any kind of base.

  • Topic: Oxidation.

  • Why do papers turn yellow?

  • They really do.

  • You don't believe me?

  • Alright.

  • Then why don't you spray some oxygen on the papers?

  • See, I was correct.

  • Do you know why this happens?

  • This happens mainly because of oxidation.

  • Oxidation is a chemical process in which a substance combines with oxygen.

  • Now, paper is primarily made up of wood.

  • Wood is made up of cellulose and lignin.

  • Now, these two components which are present in paper are susceptible to oxidation.,

  • That is, when they are exposed to air, they are likely to combine with oxygen.

  • Causing the color of paper to change from white to yellow.

  • But did you know that newspapers turn yellow relatively quickly as compared to books?

  • This is because there is more lignin in newspapers than in papers made for books.

  • Lignin is more susceptible to oxidation as compared to cellulose.

  • Hence, newspapers turn yellow faster than papers of books.

  • Topic: Oxidation.

  • Why do copper vessels turn green?

  • Wow.

  • What a beautiful copper statue.

  • Have you made it?

  • Good job.

  • But why did you use copper to make the statue?

  • It will turn green after a while.

  • No No.

  • It will not happen immediately.

  • It will take some time.

  • Look.

  • I had told you earlier.

  • Do you know why this happened?

  • This happened because of oxidation.

  • Do you know what oxidation is?

  • It is a process in which a substance gains oxygen.

  • When the copper statue was exposed to moisture and air for a long period of time, it started to get oxidized.

  • In the oxidation process, its color started changing to blackish brown and then eventually into green.

  • The green layer of color appeared because of a number of chemical reactions that took place when exposed to moisture and air.

  • This green layer formed is called patina.

  • No No.

  • Don't worry.

  • Patina does not damage the statue.

  • Patina is just a layer on top of the metal.

  • It protects the copper beneath from further oxidation, thus keeping the properties of copper intact.

  • Topic: Cleansing ability of Soap.

  • Why is soap ineffective in hard water?

  • Wow.

  • What a beautiful painting.

  • But look at your clothes.

  • They have become so dirty.

  • Why don't you wash them?

  • No No.

  • Don't use that water along with soap.

  • Please listen.

  • Fine, then bear the consequences.

  • See, you are not able to clean them.

  • Do you know why?

  • This is because you used hard water to clean your clothes.

  • Do you know what hard water is?

  • Hard water is the water which contains high amounts of minerals, such as calcium and magnesium, in the form of ions.

  • So, are these ions of the hard water responsible for soap to be ineffective?

  • You are right.

  • Now, to understand what actually happened, let us recall the activity.

  • Initially, you drenched your clothes in hard water and then you applied some soap.

  • When we apply soap, it reacts with the calcium and magnesium ions of hard water to form insoluble precipitate called scum.

  • Scum sticks to the clothes, restricting the cleansing ability of the soap.

  • Topic: Sublimation.

  • Why do mothballs disappear over time?

  • Wow.

  • You have a nice collection of clothes.

  • But have you kept mothballs to protect them?

  • I had kept them a few months back below these clothes.

  • No.

  • Where did the mothballs go?

  • I had placed them right here.

  • Did you steal them?

  • No No.

  • I haven't stolen anything.

  • Mothballs disappear over time.

  • Do you know why?

  • It is because of a process called sublimation.

  • During sublimation, a solid on heating, converts directly into vapor without passing through the intermediate liquid state.

  • Don't lie.

  • How is that even possible?

  • See, I also hid a burger here many days ago.

  • It did not disappear.

  • Gross.

  • Just throw that burger in the dustbin.

  • Not all substances sublimate.

  • Mothballs are made up of naphthalene.

  • Naphthalene has very weak intermolecular forces.

  • Because of these weak forces, the mothball which is made up of naphthalene sublimates, that is, it changes its state from solid to vapor.

  • Now, this vapor is either absorbed by the fabric or it escapes into the atmosphere causing the mothballs to disappear over time.

  • Topic: Latent heat of vaporization.

  • Why do wet clothes feel cold?

  • Because, because.

  • I don't know.

  • It is because of latent heat of vaporization.

  • Latent heat of vaporization is the amount of heat energy required to change a unit mass of liquid into vapor.

  • Now, the value of latent heat of vaporization of water is very high.

  • Is it higher than Mount Everest?

  • No.

  • The latent heat of vaporization of water is about 22 point 6 times 10 to the fifth joules per kilogram.

  • This means it is smaller.

  • Please listen.

  • This means only 1 kilogram of water requires 22 point 6 times 10 to the fifth joules of heat energy to change to vapor.

  • Now, when we wear wet clothes, the water present in them absorbs quite a lot of latent heat from our body and evaporates into the atmosphere, making us feel cold.

  • Topic: Latent Heat of Vaporization.

  • Why does steam cause more severe burns than boiling water?

  • It is because steam is jealous of boiling water.

  • No.

  • It is because of latent heat of vaporization.

  • Latent heat of vaporization is the amount of heat energy required to change a unit mass of liquid into vapor at atmospheric pressure at its boiling point.

  • Trust me.

  • Everything just went over my head.

  • Alright.

  • I will explain it to you.

  • Boiling water contains only a specific amount of heat energy required for it to boil.

  • However, as steam is formed from boiling water.

  • It contains the heat energy of boiling water, along with the latent heat of vaporization.

  • Hence, as steam has more heat energy, it can cause more severe burns than boiling water.

  • Topic: Osmosis.

  • How do fish drink water?

  • That's easy.

  • Using a straw.

  • No.

  • Fish take in water usually through their mouth or gills, depending on whether they live in freshwater or saltwater.

  • Freshwater fish takes in water mainly through its gills.

  • But Why?

  • Because it has less water and more salt concentration in its blood than the surrounding water.

  • Hence, due to osmosis, water from the surrounding flows through the gills into its bloodstream.

  • However, as the fish is continuously taking in water, it urinates a lot and removes excess water.

  • Saltwater fish takes in water through its mouth.

  • Really.

  • This is because its blood has more water and less salt concentration than the saltwater around it.

  • Hence, to maintain the balance, the fish gulps saltwater through its mouth.

  • Filters the water for its use and expels excess salt while urinating.

Topic: Neutralization Reaction.

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B2 US water latent oxidation turmeric heat acid

How to treat a bee sting? plus 9 more videos.. #aumsum

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    AumSum posted on 2019/04/13
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