Compounds and Mixtures and Earth Science Autumn Term - Year 8 Name: ____________________________________________ Teacher: __________________________________________ Question 1 (5 marks): For each of the following substance, write down whether they are elements, mixtures or compounds: Substance Oxygen Carbon Dioxide Copper Air Water Element, Mixture or Compound? Element Compound Element Mixture Compound Question 2 (3 marks): Write the letter of the diagram in the table: Description Molecules of an element Diagram Letter A – all the same atom Molecules of a compound D – different atoms joined together A mixture of different elements C – same atoms bonded. (B also has a compound present) Question 3 (2 marks): What is the difference between a mixture and a compound? A compound is when two or more different elements are chemically bonded together and are difficult to separate. A mixture is when two or more different substances are not chemically bonded together and can easily be separated. Question 4 (2 marks): 2 marks for all 4 correct, 1 mark for 2/3 correct Name the four layers of the Earth: Crust Mantle Outer Core Inner Core Question 5 (2 marks) How are igneous rocks formed? When magma from inside the Earth cools and solidifies. Question 6 (1 mark): This rock has cooled down slowly. How do we know this? There are large crystals present – the slower the cooling down, the larger the crystals Question 7 (5 marks): Look at the following statements. Tick (√) if they are true or cross (x) if they are false: Statement Limestone is a sedimentary rock Sedimentary rocks are the softest type of rock Sedimentary rocks are formed from heat and pressure Acid rain is an example of physical weathering Tectonic plates move by conduction True (√) or False (x) True True False – formed by layers of sediment and compressed False – chemical weathering False
