Elements (6.1) PDF

Pearson Science 8 - page 246 Ms Nikhat Differences between elements, compounds and mixtures can be described at a particle level (ACSSU152) § Model the arrangement of particles in elements and compounds § Describe elements and simple compounds by symbols and formulas § Locat...

Pearson Science 8 - page 246 Ms Nikhat Differences between elements, compounds and mixtures can be described at a particle level (ACSSU152) § Model the arrangement of particles in elements and compounds § Describe elements and simple compounds by symbols and formulas § Locate elements on the periodic table § Describe some common chemical elements § Recall that each chemical element is identified with a unique atomic number, which is equal to the number of protons in its nucleus § Atoms are the smallest building blocks of all matter § Different combinations of atoms create different substances § Elements are substances that are made up of one type of atoms 1. Atoms make up matter 2. All the atoms in an element are identical 3. An element is a pure substance 4. Elements can be broken into simpler substances 5. Each element is made up of the same type of atom  ELEMENTS METALLIC NON-METALLIC ELEMENTS ELEMENTS Iron Carbon Copper Sulphur Aluminium Iodine § Properties of metals: § Shiny (lustrous) § Solid at room temperature (except mercury) § Good conductors of heat and electricity (heat & electricity can pass through them) § Malleable (can be bent and hammered into sheets) § Ductile (can be stretched into wires) § Properties of non-metallic elements: § Not shiny (dull) § Solid or gas at room temperature (except bromine, which is liquid) § Insulators of heat and electricity (heat or electricity cannot pass through) § Brittle (can be easily broken) § Non-metals may have very different properties (e.g. water) § There are 118 known elements § 98 of them occur naturally § Each element has a name and a chemical symbol § Thismakes communicating new scientific research between scientists much clearer and more accurate § Atoms can exist as… § Arrangement of the atoms determine the many physical properties of the element such as state of matter (solid, liquid, gas), melting and boiling points, conductivity and strength § Monoatomic elements are elements that is made up of many individual atoms § E.g.Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe) and Radon (Ra) § These elements are all non-metallic gases § Molecules are clusters of two or more atoms bonded (joined) together § In a molecular element, all the molecules are identical, with the same size, shape, number and type of atoms 1. If a substance contains only 1 type of atom, then it’s an ELEMENT 2. If an element consists of individual atoms, then it’s an ATOMIC ELEMENT 3. If an element consists of more than one atom bonded together, then it’s a MOLECULAR ELEMENT § Canyou identify any atomic elements? § Canyou identify any molecular elements? § Crystal lattices are large grid-like structures § All metallic elements form crystal lattices § Only a few non-metals have a lattice structure § Atoms in metals form lattices § The lattice structure makes metals dense, strong and solid at room temperature § Atoms in metallic lattices can slide and move over each other without breaking the lattice, therefore metals can be bent, drawn into thin wires (ductile) or hammered into thin sheets (malleable) § Only a few non-metallic elements form lattices § Model the arrangement of particles in elements and compounds § Describe elements and simple compounds by symbols and formulas § Locate elements on the periodic table § Describe some common chemical elements § Recall that each chemical element is identified with a unique atomic number, which is equal to the number of protons in its nucleus § Module 6.1 Review Questions § Q 3-6, 9, 12 and 17 § Page 255