Sodium thiosulphate investigation Essay Example for Free

Sodium thiosulphate investigation Essay What is the middle of the atom called? The nucleus. 2 What two types of particle are found here? Protons and neutrons. 3 The electrons are arranged in shells (also called energy levels). How many can be held in the first shell? Two. 4 How many can be held in the second shell? Eight. 5 How many can be held in the third shell? Eight. 6 Where are the non-metals located in the periodic table? In the top right-hand corner. 7 What are the horizontal rows in the periodic table called? Periods. 8 What are the vertical columns called? Groups. 9 What is the name of Group 1? The Alkali Metals. 10 What is the name of Group 7? The Halogens. 11 What is the name of Group 0? The Noble Gases. 12 Elements in the same group have the same number of what? The same number of outer electrons. 13 Do elements in the same group have similar chemical or similar physical properties? Similar chemical properties. 14 Elements in the periodic table are arranged in order of what? Increasing atomic number. 15 Which of these elements has the greatest atomic number? Element B. 16 What is the electron arrangement of element C? 2. 8. 7 17 What is the electron arrangement of element E? 2. 8. 1 18 Which of the elements are very reactive metal and why? Elements D E they are in Group 1 (The alkali metals). 19 Which of the elements is a very unreactive non-metal and why? Element F it is in Group 0 (The noble gases). 20 Name the first four halogens. 1. Fluorine 2. Chlorine 3. Bromine 4. Iodine 21 What happens to the reactivity of the halogens as you go down the group (increasing atomic number)? They become less reactive. 22 What happens to the colour of these elements down the group? They become darker in colour. 23 What happens to the boiling point of these elements down the group? Their boiling points increase. 24 What does fluorine look like? A pale yellow gas. 25 What does chlorine look like? A green gas. 26 Name two uses for chlorine. 1. Killing bacteria in water. 2. Making bleaches. 27 What does bromine look like? A red -brown liquid (which evaporates easily to make an orange-brown gas). 28 What colour is bromine dissolved in water? Orange-brown. 29 What is the name of the compound formed when potassium reacts with bromine? Potassium bromide. 30 What colour is this compound when dissolved in water? Colourless. 31 What does iodine look like? A shiny grey-black solid (which produces a purple gas when gently heated). 32 What colour is iodine dissolved in water? Brown. 33 What is this iodine solution used for? An antiseptic. 34 What is the name of the compound formed when sodium reacts with iodine? Sodium iodide. 35 What colour is this compound when dissolved in water? Colourless. 36 What is the name of compounds of the halogens? Halides. 37 List two observations when sodium reacts with chlorine. 1. The metal burns with a yellow flame. 2. A white solid is produced. 38 What is the name of the product of this reaction? Sodium chloride. 39 What is its chemical formula? NaCl 40 List two observations when iron wool reacts with chlorine. 1. The metal glows red. 2. A brown solid is produced. 41 What is the name (and chemical formula) of the product this time? Iron chloride (FeCl3). 42 What is formed in this reaction: bromine + potassium iodide? potassium bromide + iodine 43 Which of these compounds will NOT react with chlorine: a) sodium fluoride; b) potassium bromide? sodium fluoride (Chlorine is less reactive than fluorine and so cannot displace it from fluorides. ) 44 What is a compound? A substance made by chemically joining two or more elements together. 45 Compounds have similar properties to the elements they are made from. Is this true or false? False they have completely different properties, eg sodium chloride is nothing like either sodium or chlorine. 46 What is the name for the substances on the left of a chemical equation? The reactants (or starting materials). 47 What is the name for the substances on the right? The products. 48 What do the symbols (s), (l) and (g) stand for in chemical equations? Solid, liquid and gas 49 What does the symbol (aq) stand for in chemical equations? Aqueous (which means dissolved in water). 50 What is meant by reaction rate? How fast a reaction goes. 51 List four ways of increasing the rate of a reaction. 1. Increasing the temperature. 2. Increasing the concentration of a reactant. 3. Increasing the surface area of a solid. 4. Adding a catalyst. 52 What is a catalyst? A chemical which speeds up a reaction but which does not get used up. 53 Does the catalyst appear in the chemical equation for the reaction? No (because it does not get used up). 54 What are enzymes? Catalysts produced by living things. 55 Why dont enzymes work if the temperature is too high? They become denatured (damaged) by the heat. 56 What two things about line A show that it represents a faster reaction? 1. It starts more steeply. 2. It levels off sooner. 57 How can you tell that both lines A and B were obtained using the same amounts of the reactants? They both produced the same amount of product in the end. 58 Increasing the temperature makes the particles move around more quickly. Give two reasons why this makes the reaction faster. 1. The collisions occur more often. 2. More of the collisions have enough energy to lead to a reaction Show preview only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.