C5 Chemicals of the natural environment Activity AC5.A.1 Elements, compounds, and molecules Cover A To answer 1 The table provides some information about different chemicals. For each of the following questions, there may be more than one answer. Name Formula Melting point (°C) Boiling point (°C) carbon monoxide CO 205 191 magnesium chloride MgCl2 714 1418 methane CH4 182 161 nitrogen N2 210 196 nitrogen monoxide NO 163 151 oxygen O2 219 183 potassium bromide KBr 730 1435 sodium chloride NaCl 808 1465 sulfur dioxide SO2 75 10 water H2O 0 100 Which of the chemicals is: a a non-metallic element? b a compound made from two non-metallic elements? c a compound made from a metal and a non-metal? d a gas at room temperature, 15 °C? e a solid at 15 °C? f a liquid at 15 °C? g made up of small molecules? h made of a giant ionic structure? i a good conductor of electricity when liquid? © University of York (UYSEG) and the Nuffield Foundation C5.A-3 This page may be copied solely for use in the purchaser’s school or college C5 Chemicals of the natural environment Activity AC5.A.1 Elements, compounds, and molecules Cover A 2 Ar O2 N2 CO2 Ar2 CO CH4 O H2O N Na NO Select the correct symbol(s) or formula(s) from the box for: a a nitrogen atom b an oxygen molecule c a metal atom d compounds e a gas that makes up 1% of the atmosphere f a molecule that is present mainly in the hydrosphere 3 a Which diagram above best represents an oxygen molecule? b Which diagram above best represents a water molecule? c Draw a diagram to represent a nitrogen molecule © University of York (UYSEG) and the Nuffield Foundation C5.A-4 This page may be copied solely for use in the purchaser’s school or college