Materials

This chapter discusses the components of matter. Matter is composed of atoms, molecules, etc. Elements combine in different proportion to give different compounds. A molecular formula explains the composition of a compound.

This chapter deals with plant and animal fibres. It also briefly explains the different types of wool such as Cashmere, Angora, Mohair, Yak wook, etc. The process of obtaining silk yarn and the life cycle of a silk moth are discussed here in detail.

This chapter explains the term heat, which is a form of energy. Heat produces different effects on solid, liquid, and gas. It causes expansion. It can be measured in Celsius and Fahrenheit scale.

This chapter discusses the heat transfer mechanism. They are conduction, convection, and radiation. There are materials which conduct heat and others which don’t. The concepts are explained with the help of experimental activities.

This chapter deals with acids, bases, and salts. Acids may be mineral or organic; however, mineral acids are strong. Bases are also characterized as strong or weak. There are numerous uses of acids and bases. Acid and base neutralise each other.

This chapter discusses the various physical and chemical changes brought about by various chemical reactions. It discusses in detail rusting of iron, evolution of gas during reaction, etc. It also discusses the various types of chemical reactions.