Flashcards
Chemistry: Redox Reactions: Oxidation and reduction in terms of electrons; Oxidising agents and reducing agents
Flashcards do conjunto (21)
- 1OxidationAddition of oxygen
Loss of electrons
Increase in oxidation number - 2ReductionRemoval of oxygen
Gain of electrons
Decrease in oxidation number - 3OIL RIGOxidation is loss (of electrons)
Reduction is gain (of electrons) - 4Oxidising AgentA species (atom, molecule or ion) that oxidises another species by removing one or more electrons. When an oxidising agent reacts is gains electrons and is, therefore, reduced.
- 5Reducing AgentA species that reduces another species by adding one or more electrons. When a reducing agent reacts it loses electrons and is, therefore, oxidised.
- 6Redox ReactionA reaction that involves both reduction and oxidation
- 7In the following equation is Oxygen reduced or oxidised? 2Mg + O2 -> 2MgOReduced - it has gained electrons according to the half equation:
O2 + 4e- -> 2O2- - 8DisproportionationA redox reaction where atoms of the same element are simultaneously oxidised and reduced.
- 9Oxidation NumberThe charge that an ion has or the charge that it would have if the species were fully ionic, represented by a symbol (+ or -) followed by a number unless 0
- 10State three rules for determining oxidation number.Any of the following:
The oxidation number of an uncombined element is 0; the sum of the oxidation numbers of all the elements in a neutral compound is zero or in an ion is equal to the charge of the ion; the more electronegative element in an substance is given a negative oxidation number; the oxidation number of fluorine is always -1; the oxidation number of hydrogen is +1, except when combined with a less electronegative element when it becomes -1; the oxidation number of oxygen is -2, except in peroxides where it is -1 and when combined with fluorine when it is positive - 11What are the oxidation numbers of the elements in the following ion: (SO3)2-Sulphur: +4
Oxygen: -2 - 12What are the oxidation numbers of the elements in the following ion: [CuCl4]2-Copper: +2
Chlorine: -1 - 13What are the oxidation numbers of the elements in the following ion: H2O2Hydrogen: +1
Oxygen: -1 - 14State the change in oxidation number to zinc in the following ionic half-equation and state whether zinc has been oxidised or reduced: Zn(s) -> Zn2+(aq) + 2e-0 to +2
Oxidised - there is an increase in oxidation number - 15State the change in oxidation number to manganese in the following ionic half-equation and state whether manganese has been oxidised or reduced: MnO4- + 8H+ + 5e- -> Mn2+ + 4H2O+7 to +2
Reduced - there is a decrease in oxidation number - 16Is the following reaction an example of a disproportionation reaction? Mg + 2HCl -> MgCl2 + H2No
- 17Is the following reaction an example of a disproportionation reaction? 2H2O2 -> 2H2O + O2Yes
In H2O2 the ox. number of O is -1.
This is oxidised to 0 in O2 but reduced to -2 in H2O, hence the reaction is disproportionation. - 18What is a systematic name?A systematic name of a compound is the name of the compound which specifies the oxidation number of an element using roman numerals in brackets. This is often used for transition metals as opposed to other species as transition metals exist in more than one oxidation state.
- 19What is the oxidation state of copper in copper (II) oxide?+2
- 20What is the oxidation number of lead in lead (IV) oxide?+4
- 21Combine the following ionic half-equations: 1. MnO4- + 8H+ + 5e- -> Mn2+ + 4H2O 2. H2O2 -> 2H+ + O2 + 2e-2MnO4- + 6H+ + 5H2O2 -> 2Mn2+ + 8H2O + 5O2
Informações
- Descrição
- Both topics (oxidation and reduction in terms of electrons, and, oxidising agents and reducing agents) from Topic 3, redox reactions, in the inorganic section of the Year 1 Edexcel Chemistry syllabus.
- Criado por
- Phoebe Johnson · jan 2017
- Atualizado
- 5 jan 2017
- Visualizações
- 80
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