All the objects around us are made of some kind of matter. All kinds of matter possess mass and occupy space, so matter is defined as anything which has definite mass and occupies space. Matter exists as solids, liquids and gases, and in any physical state it is composed of smaller particles such as atoms, molecules or ions. Atoms are the building blocks of matter. This chapter covers symbols of elements, metals, non-metals and metalloids, compounds in the three states, and the uses of compounds in daily life.
1. Matter and Its Particles
- We perceive objects through our senses: a glass tumbler can be seen, burning agarbatti is recognised by its smell and blowing wind can be felt.
- Atom – the smallest particle of an element which exhibits all the properties of that element.
- Molecule – formed when atoms of the same element or different elements combine.
- Ions – atoms or groups of atoms having a charge (positive or negative).