Plants and mankind, characteristics of plants, structure and function of plant cells and organelles;

  Objects having characteristics of cellular organization, growth, reproduction, ability to sense environment and give response are living organisms. There are some important features of living organisms: It should grow, which means its structure changes as time goes by in an advantageous manner. It should show adaptation to the environment. It should maintain some balanced … Read more

Preparation of Oxygen

Preparation of Oxygen Oxygen is prepared in lab generally in two ways either by the application of heat or no application of heat. Using heat: Oxygen in lab is prepared by heating the mixture of powdered potassium chlorate and manganese dioxide in the ratio 4:1 in a hard glass test tube. The oxygen gas is … Read more

Preparation of nitrogen

  Preparation of nitrogen Nitrogen is found in both free and combined states. It occupies 78.07% by volume. Nitrogen can be prepared: By heating copper in air: Firstly, air is passed through lime water and then concentrated sulphuric acid to make the air free from carbon dioxide and moistures respectively. The air contains only nitrogen … Read more

Structure and function of animal cell and cell organelles

  Objects having characteristics of cellular organization, growth, reproduction, ability to sense environment and give response are living organisms. There are some important features of living organisms: It should grow, which means its structure changes as time goes by in an advantageous manner. It should show adaptation to the environment. It should maintain some balanced … Read more

laboratory method of preparing alcohol

Laboratory method of preparing alcohol Hydrolysis of Alkyl Halides This is a nucleophilic  substitution reaction. R-X + KOHaq → R-OH The method is not satisfactory as olefins are also formed as by-products. However better yields is obtained by using moist Ag2O or aqueous K2CO3. Tertiary butyl halides mainly gives alkene due to dehydrohalogenation. Hydration of Alkenes This … Read more

Basic concepts of ecosystem

Eco-System-An ecosystem is defined as a structural and functional unit of biosphere consisting of community of living beings and the physical environment, both interacting and exchanging materials between them. It includes plants, trees, animals, fish, birds, micro-organisms, water, soil, and  people. When an ecosystem is healthy (i.e. sustainable) it means that all the elements live … Read more