Download Electrolysis Test Study Guide 2024 and more Exams Nursing in PDF only on Docsity! Electrolysis Test Study Guide What are the 8 uses of electrolysis? - Answer- Purification of metals Electroplating Chlorine production Extraction of Hydrogen from water Extraction of oxygen from water Extraction of Reactive metals Hair removal Production of sodium hydroxide What is Electrolysis? - Answer- The passing of an electric current through an molten ionic compound causing a chemical change resulting in a change in the elements that make up the compound. What is an Electrolyte? - Answer- A molten ionic compound that undergoes electrolysis. What is an Anode? - Answer- A positively charge electrode. What is a Cathode? - Answer- a negatively charged electrode. What is an electrode? - Answer- an electrical conductor. (Chem web def: Terminals/sticks that allow electricity to go through them.) What are the Diatomic elements? - Answer- H, N, O, F, Cl, Br,I Or H-NOF-I What Does being a Diatomic element mean? - Answer- This means that a when a comped is split up, and one of the products of the reaction is a diatomic element then that diatomic element has X₂ Tip: When a compound is spilt up, if it becomes a diatomic element and a metal, the diatomic element will be a gas (g), while the metal will be a solid (s). What are the charges of the elements On the periodic table in Groups 1, 2, 3, 5, 6, 7 - Answer- Groups: 1 = +1, 2 = +2, 3 = +3, 5 = -3, 6 = -2, 7 = -1, (group 4 is neutral) What are the steps for electrolysis? - Answer- 1. Draw the two electrodes and display their two charges. a. Electrode is an electric conductor. b. Their must be a positive (anode)and negative conductor (cathode) 2. Write down the ions that are present with in the electrodes. a. You must display the charges on the ions. b. Hint: Group 1 (+1), 2 (+2) , & 3 (+3) have the charges +1, +2, +3 respectively c. Group 7 (-1), 6 (-2) & 5 (-3) ions have the charges -1, -2, -3 respectively. 3. Show the movement of the ions to their respective electrodes 4. Represent the ions present at each electrode. a. At cathode (-) Na+ b. At anode (+) Cl- 5. Complete the equation showing how the ion is discharged to form the natural element. a. At cathode (-) Na+ Na(s) b. At anode (+) Cl Cl (g) 6. balance the equations (& check for diatomic elements) a. At cathode (-) Na+ Na(s) b. At anode (+) 2Cl(-2e) Cl(2) (g) c. Only balance half equations separately (not to get her). KI(L) --> NaBr(s) --> LiCl(l) --> - Answer- KI(l) --> K(s) + I2(g) NaBr(s) --> No Reaction LiCl(l) --> Li(s) + Cl2(g) Show the steps for this equation MgCl2 --> - Answer- Go to http://trevor.mrooms.org/mod/page/view.php?id=32401 to check the answer! Need to know - Answer- Electrodes can ONLY discharge 1 ion. Sometimes there are more than 1 ion at an electrode. In this case, the electrode discharges the ion that is more readily discharged. For negative ions (-ions), the higher up the electrochemical series, the more readily discharged. For positive ions (+ions), the lower down the electrochemical series, the more readily discharged. In the Electrochemical Series For ________ ions (_ions), the higher up the electrochemical series, the more readily discharged. For _____ ions (_ions), the lower down the electrochemical series, the more readily discharged. - Answer- Negative, Positive How do you know when to use the electrochemical series? (FOR THIS TEST ONLY) - Answer- (normally it would be if there are more than 2 elements in a compound but for this test) When you see (aq) it means aqueous solution. Since aqueous solutions means dissolved in water, water is a component to problems with (aq).