B. Answer
Briefly
1. Why do you need to group or classify things around you?
2. What are soluble and insoluble materials ?
3. Name two substances which are soluble and two substances which are insoluble in water?
4. What happens when chalk powder and sand are added to water? Why?
5. What happens when salt and lime juice are added to water? Why?
6. What happens when kerosene oil and cooking oil are added to water? Why?
7. What is transparency?
Answers
Explanation:
1-we need to group or classify things around you because it makes things easier and simpler. you can do things in an organized way.
2-We have a word for substances that form solutions when they are mixed with water. These substances are called soluble substances. Substances that do NOT form solutions when they are mixed with water are called insoluble substances.
3-Sugar and salt are examples of soluble substances. Substances that do not dissolve in water are called insoluble. Sand and flour are examples of insoluble substances.
4-Chalk doesnot dissolve in water. Chalk comprises CaCO3 which is insoluble in water because the forces of attraction between calcium and carbonate ions are stronger than ions of calcium carbonate and water.
5-Lime juice squeezed in water with a pinch of salt and sugar contains natural electrolytes. These electrolytes help replenish the sodium and nutrient content in the body. It hydrates the body efficiently and prevents the effects of dehydration like muscle cramps and fatigue.
6-You will get a layer of kerosene and a layer of denser water under it. The two do not mix well but the water will dissolve a tiny amount of kerosene, enough to taint it and the kerosene will dissolve some water, enough to make it sputter a little if burned in a lamp.
7-Transparency, as used in science, engineering, business, the humanities and in other social contexts, is operating in such a way that it is easy for others to see what actions are performed. Transparency implies openness, communication, and accountability.