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Showing posts from July, 2016

The Kinetic Theory of Matter & Gases

The Kinetic Theory of Matter postulates that matter is made up of tiny particles that are continuously in motion and so possess kinetic energy . It is also known as the Molecular Theory. The particles may be atoms, molecules or ions. Recall that matter exists in three common states, namely solid, liquid and gaseous states; although, we also have plasma and Einstein-Bosé condensate as additional states of matter. However, these are beyond our scope of discussion. The major differences in the properties of solid, liquid and gas are the degrees of intermolecular forces of attraction and average kinetic energy of the particles. While the intermolecular force is strongest in the solid state, which confers upon a solid its rigidity in shape and form, it is weakest in the gaseous state, which explains why a gas is formless and takes the shape and volume of the containing vessel. The intermolecular force of attraction is however, mild (not very strong and not very weak) in the liquid sta...

Gas Laws (Part I): Boyle's Law. Charles' Law. Dalton's Law of Partial Pressure

Gas Laws These are empirical laws that are used to explain the behaviour of ideal gases. An ideal gas is a perfect gas. It is a gas that does not exist, because there is no perfect situation in the real world. The Gas laws are grouped into two major categories - the physical and chemical laws. The former seek to explain the behaviour of gases based on their physical properties such as volume, temperature and pressure, while the latter do so by using their chemical properties like the number of molecules in the gases. We had looked at the chemical laws in our post - Gas Laws (Part II): Gay Lussac's & Avogadro's Laws , so this post will be devoted to the discussion on the physical laws. Boyle's Law This law states that the volume, V, of a given mass of gas is inversely proportional to its pressure, P, provided the temperature remains constant. This implies that if the volume of a gas is doubled, it will lead to a decrease in the gas pressure by half. Simil...