Year 8 Chemistry Atoms and Elements 2024 PDF

Atoms and Elements make up matter Lesson 1 – Year 8 Chemistry 2024 Success criteria Define and describe the key features of periodic table including periods, groups, elements, monatomic gases and diatomic gases Relate the atomic number and mass number of an element to the number of su...

Atoms and Elements make up matter Lesson 1 – Year 8 Chemistry 2024 Success criteria Define and describe the key features of periodic table including periods, groups, elements, monatomic gases and diatomic gases Relate the atomic number and mass number of an element to the number of subatomic particles. Learning Intentions all matter is made up of atoms. an element is a pure substance with one type of atom. the periodic table organises elements according to their chemical and physical properties.  Glossary Terms Atom the smallest particle of matter; cannot be created, destroyed or broken down (indivisible) Monatomic consisting of a single atom diatomic molecule a molecule that consists of two atoms periodic table a table in which elements are listed in order of their atomic number, and grouped according to similar properties period (in chemistry) a horizontal list of elements in the periodic table Group (in chemistry) a vertical list of elements in the periodic table that have characteristics in common What is stuff made from? The atom is the smallest particle of matter. It cannot be created or destroyed or broken down further. Atomic Structure The nucleus makes up most of the atom’s mass. It consists of positively charged protons and uncharged neutrons. Surrounding the nucleus are negatively charged electrons. What are elements? An element is a pure substance that it only made of one type of atom. For example: The element Helium can only be made of Helium atoms. The element Oxygen can only be made of Oxygen atoms. Molecules A molecule is a group of two or more atoms bonded together. Something can be a molecule and an element at the same time. For example: oxygen gas has two oxygens so is both a molecule and an element. Other words we can use to describe elements and molecu Mono – one Di – two Monoatomic – consisting of a single atom. Diatomic – a molecule that is made from two atoms  Elements cannot be broken down anymore because they are already in their simplest state. Propertie s of All elements have different properties and structures. elements There are two main groups of elements metals and non-metals.  Metals Non Most metals are solid Most non-metals are at room temperature gasses at room Atoms of metals tend temperature to form in a lattice structure The Periodic Table – An organisation tool for elements Arranges all of the elements based on the SIZE of the atoms. All elements represented by their symbol. Symbols are always capital letters (with a lowercase letter second if there is one).  Number of protons The average mass of atoms of that element (mass of protons, neutrons and electrons) The Periodic Table – Periods and Groups Note: Elements in the same group on the periodic table have similar properties Everything on the periodic table is electrically neutral Each element has a unique number of protons – this is its atomic number. E.g. Oxygen has an atomic number of 8 so every oxygen atom must have 8 protons in its nucleus To balance these positive charges, the atom must have 8 electrons around the nucleus. We then say the atom is electrically neutral. Elements on the periodic table are arranged by atomic number. First 20 Elements – In this unit, we will mainly be talking about the first 20 elements on the periodic table. You don’t need to memorise them, but knowing their names and their symbols will be helpful https://www.youtube.com/watch?v=PGid34_Lss0 Write down the full names of each element according to their atomic number Lesson Summary All matter is made up of atoms An element is a pure substance with one type of atom The periodic table organises elements according to their chemical and physical properties  5.1 Check your learning Remember and understand 1 Compare the difference between atoms and elements. 2 Identify the two large groups in the periodic table. 3 Identify the name given to the rows of the periodic table. 4 Identify the names and symbols of the first five elements in the periodic table. Apply and analyse 5 Identify the element found in period 3, group 2. 6 Identify the two letters that are not represented in the elemental symbols of the periodic table. Evaluate and create 7 Create five words using the elemental symbols of the periodic table. (An example is: Helium (He), Lithium (L) and Phosphorus (P) can spell HeLP.)