CHAPTER 20- ELECTROCHEMISTRY 🤎 Flashcards

Question 1

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IGCSE RECAP: define electrolysis, electrolyte and electrodes
-Draw and label a diagram showing parts of an electrolysis cell, indicate the direction in which electrons travel

Question 2

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Name the positive and negative electrode making up an electrolysis cell

Question 3

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Give the electrolysis products at the anode and cathode of the following compounds: molten lead (II) bromide, dilute sulfuric acid, NaCl (aq), copper (II) chloride, potassium iodide,
-List the discharge series to help you find the answer
-Write the balanced half equations when the following substances are the products: oxygen, hydrogen, silver, lead

Question 4

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Write general ionic equations for reduction at the cathode and oxidation at the anode

Question 5

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Give four definitions of oxidation and four definitions or reduction

Question 6

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Use two half equations to write a full redox equation for the reaction of MnO4- ions with Fe2+ ions

Question 7

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Write the formula for calculating the Avogadro’s constant using an electrolytic method

Question 8

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Give the following: the formula relating electric current and time, formula for Faraday’s constant, value of Faraday

Question 9

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Using a diagram, describe a standard hydrogen electrode and write it’s half equation
-What is the role of a standard hydrogen electrode?

Question 10

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Using the examples in your notes, calculate the mass of a substance deposited at an electrode AND the volume of gas produced at an electrode

Question 11

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Define the terms electrode potential and redox equilibrium
-Explain how the position of equilibrium differs between reactive metals and unreactive metals
-Using silver and zinc as examples, explain what their electrode potential tells us about how easy the ions are to reduce, reactivity of the metal, and how good of a reducing agent it is (include the position of equilibrium)

Question 12

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What is a half-cell? Give three standard conditions that must be met when making a half cell

Question 13

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Draw and describe an electrochemical cell
-At which terminal does reduction and oxidation take place?

Question 14

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Define standard electrode potential, give three standard conditions that must be met when measuring the standard electrode potential
-State the three types of electrochemical cells that can be used to measure the standard electrode potential

Question 15

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Draw and label an electrochemical cell with a half cell containing a metal and it’s metal ions, write it’s half equations, state which ions are easier and more difficult to reduce

Question 16

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Draw and label an electrochemical cell with a half cell containing a non-metal and it’s non-metal ions, write it’s half equations, state which ions are easier and more difficult to reduce

Question 17

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Draw and label an electrochemical cell with a half cell containing ions of the same element in different oxidation states, write it’s half equations, state which ions are easier and more difficult to reduce

Question 18

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Define standard cell potential (voltage)
-Give the formula for calculating cell voltage
-In an electrochemical cell, which electrode is the positive pole and which is the negative pole?
-In which direction do electrons flow in an electrochemical cell?

Question 19

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Explain how standard electrode potential values can be used to predict if a reaction will occur (4)

Question 20

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Use the reduction equations and E⦵ values of copper and zinc to determine if a reaction between the two would be feasible

Question 21

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Use the questions in your notes to practice determining feasibility

Question 22

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Explain the relationship between E⦵ values and oxidising/ reducing agents (use a summary table in your explanation)

Question 23

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Using an example equation, explain the effect of changing ion concentration on the electrode potential value (Use Le Chatelier’s principle in your explanation)

Question 24

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Write out the Nerst equation and state what each symbol in the equation stands for
-Using the example in your notes, carry out a calculation using the Nerst equation

Question 25

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Explain how to predict the products of electrolysis of pure molten ionic compounds and aqueous solutions

Question 26

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Explain the effect of ion concentration on the products of electrolysis (use the example of NaCl in your explanation)

Question 27

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Write out the Gibbs free energy equation and state what each letter represents

Question 28

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AS level recap: define equilibrium, dynamic equilibrium, Le Chatelier’s principle
-State the different rules of oxidation numbers