Elements, mixtures and compounds

Elements  Made up of only one kind of atom. There are approx 109 elements known.

Elements  Made up of only one kind of atom. There are approx 109 elements known.  Some elements exist naturally in small bonded groups called molecules, so have a different formula to that on the periodic table.

Elements  Made up of only one kind of atom. There are approx 109 elements known.  Some elements exist naturally in small bonded groups called molecules, so have a different formula to that on the periodic table. EG  H 2 is hydrogen, O 2 is oxygen etc.

Elements  Made up of only one kind of atom. There are approx 109 elements known.  Some elements exist naturally in small bonded groups called molecules, so have a different formula to that on the periodic table. EG  H 2 is hydrogen, O 2 is oxygen etc.  Elements can be classified by their state at room temperature. EG  solid, liquid or gas.

Elements  Made up of only one kind of atom. There are approx 109 elements known.  Some elements exist naturally in small bonded groups called molecules, so have a different formula to that on the periodic table. EG  H 2 is hydrogen, O 2 is oxygen etc.  Elements can be classified by their state at room temperature. EG  solid, liquid or gas.  wSKFBpo wSKFBpo

Mixtures and compounds  Substances which contain different elements are either mixtures or compounds.

Mixtures and compounds  Substances which contain different elements are either mixtures or compounds.  Mixtures – can be easily physically separated.

Mixtures and compounds  Substances which contain different elements are either mixtures or compounds.  Mixtures – can be easily physically separated.  Compounds – chemically joined together which makes it hard to separate.

Quick questions: 1. Sort into either elements or compounds: a) H 2 O b) Sugar – C 12 H 22 O 11 c) Pb d) Cl 2 e) Baking soda – NaHCO 3

Quick questions: 1. Sort into either elements or compounds: a) H 2 O b) Sugar – C 12 H 22 O 11 c) Pb d) Cl 2 e) Baking soda – NaHCO 3 Elements – Pb,Chlorine (Cl 2 ) Compounds – water, sugar, baking soda

Names  The names of a compound can tell you what elements make it up.

Names  The names of a compound can tell you what elements make it up.  If a name ends in ‘ate’ or ‘ite’ this tells you that the compound contains oxygen atoms as well as other elements named.

Sorting out chemical formula  A chemical formula is a short way of showing the numbers of each kind of atom in one molecule of compound.

Sorting out chemical formula  A chemical formula is a short way of showing the numbers of each kind of atom in one molecule of compound.  The letters show while elements make up the compound. CuSO 4 MgCl 2

Sorting out chemical formula  A chemical formula is a short way of showing the numbers of each kind of atom in one molecule of compound.  The letters show while elements make up the compound.  The numbers underneath show how many of each kind of atom make up one molecule. CuSO 4 MgCl 2