Assets, bases and salts Part 1 Hello children Assets and bases are encountered daily in our everyday lives. They are both an important part of our livelihood. We play an essential role inside or outside our body. From the formation of food to the decomposition of any substance, acids and bases have a role. Let us know about their use in our daily lives. We will go to Raju and his friends to learn more about this. The purpose of this video is to learn about acids, bases and salts. Yesterday being a festival, my mother prepared salty mixtures, pakoras, samosa and a few sweets. My mother has also prepared. However, my father fell sick in between with a lot of stomach ache and could not eat much. Wow Raju, what samosa your mother makes and her tamarind chutney, it is so tangy, spicy and tasty. My food is slightly bitter. My mother gave me the green leafy vegetable curry with the roti. I brought laddos and a little mixture. Wow, a few broad sweets, a few rotis, few green leafy vegetable curry and I brought paratha and curd. Let us eat quick and share the delicious food. We have science class immediately after the lunch break. Good afternoon children, did you all have your lunch? Yes sir. Today we brought food with different tastes, some sour, some sweet, some salty and some bitter. Children, do you all know that different foods have different tastes because of a lot of food contains acids, bases and salts. Acidic, I heard that acids are dangerous. Lata was telling me yesterday. Who know, not all acids are dangerous. Mamta make a list of the foods you eat that are mostly sour. Tamarind chutney, orange, tamarind, curd, samosa, guava, apple and… That s enough. Thank you. Do you know that all these foods contain acids which causes sourness in them. Acid in our foods? Yes, all these are natural acids. What happens when you eat food? It gets digested. Yes, your body also produces some acids and they help in digestion of food. I see. So there are some good natural acid as well. Yes, the acids that are there in our school lab are very powerful and dangerous and need to be used with caution. They are high in acidic content and low in water content. Children, the acids that are used in the labs are very corrosive and concentrated. We should never taste them as our tongues will get burnt. Sir, my father had stomach pain yesterday. When we went to the doctor, he said my father had acidity. He gave him some medicine. He said it was some antacid. Sir, does the medicine nullify the acids? Yes, due to spicy food and also flatulent food, stomach becomes acidic. And due to this, people have acidity. If we take antacids at that time, we get relief. Antacids have bases. Two bases nullify the effect of acid. Yes, we shall talk about this tomorrow. My father was feeling better after two hours yesterday, after he took the medicine. Bases are the chemical compounds, which are soapy in touch and are not usually meant for human consumption. They are better in taste. They have a wide range of applications in our daily life. They have hydroxide ions present in them, and acids have hydrogen ions present in them. Sir, can you please explain in detail? When acid dissolves in water, it releases hydrogen ions. Acids have hydrogen in them, like HCl, hydrochloric acid, H and O3 nitric acid, H2SO4, sulphuric acid etc. Sir, do bases have more hydroxide ions in them? Bases any compound that yields hydroxide ions, OH, when dissolved in water, example sodium hydroxide, NAH, OH. Magnesium hydroxide, MG OH2, Potassium hydroxide, KOH. Sir, can you please give some examples of bases? Limestone, baking soda, washing soda, all bases. Does soap also have base? Yes, soap not as a natural soap, which has a base. Mother uses soap not to wash her hair. Yes. Children, can you tell whether there are acids or bases in toothpaste, chalk piece and spinach? Sir, some items are sweet. Do they have acids or bases in them? They have neither acids nor bases. Some substances have neither acids or bases. What will happen when acids and bases get mixed? Rinku, when acids and bases meet, generally salts are formed along with water. Oh, I see. The salt we consume is formed due to combining of hydrochloric acid and sodium hydroxide. Very interesting. Sir, there must be some indicator to determine whether a substance is having acid or base. We cannot taste each and every substance to determine whether it contains acids or bases. The time is over now. Let us talk about it tomorrow. Children, we have come to know the difference between acids and bases. While acids dissolve in water, most bases do not dissolve in water. In the next video, we will learn about the indicators that determine whether substances contain acids or bases. Until then, see you.