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.
