1. Mixture vs Compound
1.1. Chemically combined
1.1.1. Molecules/compounds eg. H2O. Water can only be separated into hydrogen and oxygen by a chemical reaction. eg. 2H20 --> 2H2 + O2
1.1.1.1. Q: Capsaicin is a substance that gives chilli its hot taste. It has the formula C18H27O3N. Which of the following is not true? A: It is a mixture of 4 elements. B: There are 49 atoms in a molecule of capsaicin. C: The elements in capsaicin are non-metallic elements. D: The elements in capsaicin cannot be separated by physical methods.
1.2. Physically combined
1.2.1. Mixture. eg. salt water. (NaCl + H20) Salt and water can be separated by physical methods. eg. boiling to evaporate water.
2. Molecules
2.1. is made up of
2.1.1. Atoms
2.1.1.1. made up of 3 subatomic particles.
2.1.1.1.1. Proton
2.1.1.1.2. Neutron
2.1.1.1.3. Electron
2.1.1.2. -the smallest particle of an element. -the smallest unit of a substance.
2.1.1.2.1. same type of atoms
2.1.1.2.2. different type of atoms
2.2. is either
2.2.1. Element
2.2.1.1. -made up of atoms of the same type. -simplest form of a substance. -cannot be broken down into simpler substance.
2.2.1.1.1. eg. CH4 is a substance which can be broken down into simpler substance C and H. -C and H are elements. ie. substances of the simplest form. -C or H cannot be broken down into simpler form.
2.2.2. Compound
2.2.2.1. -made up of atoms of different elements. -can be broken down into simpler elements. (by chemical reactions). -not the simplest form of a substance.
2.2.2.1.1. eg. CH4 is a compound. made of elements C and H. eg. H20 is a compound. made up of elements H and O.