Wild Chemistry Ride 5:


Elements, Compounds and Mixtures

This was a topic which was quite confusing for some, but fortunately with prior reading I didn't find it that bad. So I've learnt that matter is classified into 3 categories: elements, compounds and mixtures. 

• Element: A substance made up entirely from only one type of atom
• Compound: A substance which is made up of two or more elements chemically combined in a fixed composition
• Mixture: A substance made-up of two or more elements or compounds not chemically combined in a fixed composition, and these components can be physically separated. 

There had been some confusion on identifying molecules, which are the smallest particles in an element or compound that has the properties of the element or compound, and they have to contain two or more atoms. And one misconception that some of us had was that a monatomic substance is a molecule, which we later learnt was untrue.

It was interesting how the atomic number was the proton number which is unique for every element, and that the number of protons is equal to the number of electrons. And as such we discovered that the number of neutrons is the proton number deducted from the mass number (which indicates the total number of protons and neutrons in an atom)