1. The diagram represents a particle of methane.(a) What is the formula of methane?..........................................................................(1)(b) Choose a word from the box to answer the question.Which of the words best describes the methane particle shown in the diagram? (1) atom ion molecule(c) Choose a word from the box to answer the question.What is the type of bonding shown in the diagram? covalent ionic metallic (1)(Total 3 marks)
Study and take notesFind out what covalent bond is and how to draw covalent bonds.
What is a covalent bond? incomplete Cl outer shells ClThe two non-metal atoms cannot form a bond by transferringelectrons from one to another. Instead, they shareelectrons. Each atom now Cl Cl has a full, stable outer shell.The shared electrons join the atoms together. This iscalled a covalent bond.
Drawing covalent bonds A covalent bond is a shared pair of electrons. Cl Cl covalent bond outer Cl – Clshell dot solid – Cl Cland cross line Cl Cl diagram
Rules of Covalent bondingo Needs 2 or more NON-METAL ATOMSo Electrons are SHARED to complete the shellso The electron shells overlap.
Drawing MolymodsTo do:Next practice drawing covalent bonds fordifferent molecules.
How many bonds? 1 2 3 4 What elements? H O N C Cl • Hydrogen (H2) •Water (H2O) • Chlorine (Cl2) •Methane (CH4) • Hydrogen chloride (HCl) •Ammonia (NH3)EXTENSION – draw O2 and CO2
Plenary – Ionic or Covalent• Using your periodic tables work out which type of bonding will be shown in these compounds! Br2 H2O Cl2 Li2O MgO HCl N2 CaCl2 CH4 NH3 NaCl• Extension– draw an ionic compound and a covalent compounds