Learning Outcomes I can identify and describe the difference between a Mixture, a Compound, an Element, Atom and a Molecule

Draw and label an atom in your jotter. Elements and Atoms All elements are made up of very tiny particles called atoms. The centre of the atom is called the nucleus. The nucleus contains particles called protons. Electrons spin round the nucleus in energy levels. Q1. What particles are found in the nucleus of an atom? Q2. What particles are found in the energy levels surrounding the nucleus? Draw and label an atom in your jotter.

More about Atoms The atoms of a particular element are all the same as they all have the same number of protons and electrons. This number is called the atomic number and it matches the position of an element in the Periodic Table e.g. hydrogen is number 1 in the table and all its atoms have 1 proton and 1 electron whereas oxygen is number 8 in the table and all its atoms all have 8 protons and 8 electrons. Q3. What number gives the position of an element in the Periodic Table? Q4. What does this number tell you about the atoms of that element? Q5. Magnesium is number 12 in the Periodic Table. How many protons and electrons does an atom of magnesium have?

Use your periodic table to copy and complete the table Name of Element Symbol of Element Number of Protons Number of Electrons carbon C 6 helium He silicon 17 Fe Au

Making Model Molecules In a model atom kit the following colour code applies. Copy the atoms into your jotters and colour them using coloured pencils. Remember to name the atoms. red for oxygen black for carbon blue for nitrogen white for hydrogen green for chlorine When atoms join together they form molecules. All the holes in the model atoms must be used up with the plastic bonds. The other ends of the plastic bonds must then be joined to other atoms.

Making Model Molecules (2) Q1. What do atoms form when they join together? Q2. how many holes does an oxygen atom (red sphere) have? How many bonds will oxygen form? Q3. How many holes does a chlorine atom (green sphere) have? How many bonds will chlorine Q4. How many holes does a nitrogen atom (blue sphere) have? How many bonds will nitrogen

Molecules of Elements Join two model atoms together to make the following molecules and draw a labelled coloured picture of each one. The first one has been done for you. A chlorine These examples all show B oxygen molecules of elements. C nitrogen We know this because the D hydrogen molecules contain only one type of atom. Q5. How many types of atom are present in a molecule of an element?

Molecules of Compounds To make models of compounds we use different coloured model atoms joined together e.g. methane is a compound formed between carbon and hydrogen. The Black sphere represents carbon. The black sphere has 4 holes which means it can form 4 bonds. Hydrogen is represented by the white sphere. Hydrogen atoms can form 1 bond.

Molecules of Compounds (2) Now join your model atoms together to make other model molecules of compounds like methane. Draw a labelled coloured diagram of each one in your jotters. A hydrogen chloride C nitrogen hydride (ammonia) B hydrogen oxide (water) D carbon dioxide Q6. How many types of atom are present in a compound?

Sorting out Elements and Compounds Put two headings in your jotter: Element and Compound Look at the molecules below and decide whether they are compounds or elements. Draw the molecules under the correct heading.

Mixture, Compound, Element, Atom or Molecule? Look at the diagrams on the next slide. Collect the diagram sheet and decide whether they show A mixture A compound An element An atom A molecule Stick the completed diagram into your jotter.

Mixture, Compound, Element, Atom or Molecule? A B C D

Mixture, Compound, Element, Atom or Molecule? Try the Power Point test for mixture, compound, element, atom or molecule?. Arrange yourselves into groups of 2. Look at each of the powerpoint pictures and discuss whether they show: A mixture A compound An element An atom A molecule

Summary When two or more elements are joined together during a chemical reaction then a new substance called a compound is formed. If elements do not react and are not joined together then a mixture is formed. All elements are made up of tiny particles called atoms. The nucleus of an atom contains protons and neutrons.

Summary (2) The energy levels surrounding the nucleus contains electrons The atomic number gives the position of an element in the Periodic Table. Atoms form molecules when they join together. Compounds have a slightly different name from the elements from which they were made. The 1st element keeps its name but the 2nd element has some of its letters changed to –ide.