2. (f.w. Some of the worksheets for this concept are Work 25, Work oxidation numbers name, Work 7, Oxidation number exercise, Redox practice work, Academic resource center, Chapter 20 work redox, Work assigning oxidation numbers. Thus a 0.10 M sugar solution contains 0.10 mole of sugar molecules per liter of solution. • Rule 4: The oxidation number of an alkali metal (IA family) in a compound is +1; the oxidation number of an alkaline earth metal (IIA family) in a compound is +2. 4.2: Oxidation Numbers, Redox Reactions, Solution Concentration, and Titrations (Worksheet), [ "article:topic", "worksheet", "Author: Robert Carter", "Guided Inquiry", "authorname:carterr", "transcluded:yes", "source-chem-81595" ], Associate Professor and Chair (Chemistry), 4.3: Balancing Redox Equations (Worksheet), Analytical Concentration vs. Actual Species Concentration, Understand the rules for assigning oxidation numbers, Understand the concepts of oxidation and reduction in terms of oxidation numbers, Understand solution concentration in terms of molarity, Know the connection between molarity, volume, and moles or millimoles of solute, Understand the difference between analytical concentration and actual species concentration, Understand the techniques of titration and the quantitative relationships on which it is based, Be able to assign oxidation numbers to elements in chemical species, Be able to identify when a species is being oxidized or reduced, Be able to calculate molarity of a solution, Be able to convert between molarity, volume, and moles or millimoles, Be able to assess the actual ion concentrations in a strong electrolyte solution, Be able to carry out stoichiometry calculations using molarities and volumes of solutions, Be able to carry out titration calculations, All simple monatomic ions have oxidation numbers equal to their charges. 3. Describe how you would go about making exactly 500 mL of 0.100 M NaNO3 (aq) solution, using reagent grade NaNO3 (s) (f.w. Which of the following has the highest concentration of sodium ion: \(0.20\, M\, NaCl\), \(0.13\, M \,Na_2SO_4\), \(0.080\, M\, Na_3PO_4\)? (e.g., all Group 1 ions are +1; all group 2 ions are +2; all the following ions have oxidation numbers given by their charges - Fe, Halogens are usually -1, except when a central atom or when combined with a more electronegative element (e.g., assign I as -1 in NI, Oxygen is -2 in most of its compounds, except in peroxides (H, Hydrogen is usually +1, except in hydrides with electropositive elements, particularly with metal cations, where it is -1 (e.g., NaH, CaH. The worksheet contains 20 examples that cover all of the oxidation number rules discussed in class. Worksheet will open in a new window. The situation is different with electrolytes, because they break up to some extent to give ions in solution. 0000005052 00000 n
Created: Oct 11, 2012. • Rule 5: The oxidation number of oxygen in a compound is usually –2. Solution concentration is a statement of the amount of solute present in a solution relative to either the amount of solvent or the amount of solution. 0000001047 00000 n
An important application of the relationships \(MV_L = mol\) and \(MV_{mL} = mmol\) is volumetric analysis, which uses precise measurement of the volume of a solution of known concentration, called a standard solution, as a means of carrying out chemical analysis. Hydrogen –usually +1, except when bonded to Group I or Group II, when it forms hydrides, -1. An important application of this is the analytical technique of titration, used to determine the amount of a substance, such as an acid or base, in a solution. 0000004893 00000 n
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Missed the LibreFest? For example, suppose we make a \(0.10\, M\, NaCl\) aquous solution; i.e., \(C = 0.10\, M\). +2 and +3 C. +1 and +3 D. +2 and +4 8. This worksheet has 4 problems to solve. xref
All of the \(NaCl(s)\) breaks up to dissolve as \(Na^+ (aq)\) and \(Cl^– (aq)\) ions: From this we can say, \([Na^+ ] = 0.10\, M\), \([Cl^– ] = 0.10 \,M\), and the concentration of all ions (both cations and anions) is 0.20 M. Consider the same analytical concentration of \(Na_3PO_4\). 2Fe(s) + 3Cl2(g) → 2Fe3 + + 6Cl −. Updated: Jan 15, 2013. docx, 770 KB. The Oxidation Number Of A Monatomie Ion Equals That Charge On The Ion 3. Assign the oxidation numbers of each element in the following chemical species: HCl, H2O, NH3, NO3–, K2Cr2O7, Hg2Cl2, HgCl2, Al(OH)3, Na3PO4. Titration is often used to determine the concentration of a solution of an acid or base, employing the stoichiometry of a neutralization reaction. Oxidation number rules: Elementshave an oxidation number of 0 Group Iand II– In addition to the elemental oxidation state of 0, Group I has an oxidation state of +1and Group II has an oxidation state of +2. When a species is reduced, one of its atoms goes to a lower (less positive or more negative) oxidation number. %PDF-1.4
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For example, if the analyte is a monoprotic acid and the titrant is a standard solution of NaOH(aq), the millimoles of acid initially present will be equal to the millimoles of NaOH(aq) added to reach the equivalence point, because the stoichiometry between moles of analyte and moles of titrant is 1:1. Write the oxidation number above each element. \(Zn(s) + 2 HCl(aq) \rightarrow ZnCl_2(aq) + H_2(g)\), \(Fe_2O_3(s) + 2 Al(s) \rightarrow 2 Fe(s) + Al_2O_3(s)\), \(14 HNO_3 + 3 Cu_2O \rightarrow 6 Cu(NO_3)_2 + 2 NO + 7 H_2O\), \(I^– + 2 MnO_4^– + H_2O \rightarrow IO_3^– + 2 MnO_2 + 2 OH^–\). By either definition, the numerical value of the molarity of a particular solution is the same. In essence, the Fe "pushes" electrons and the Cl 2 "pulls" electrons, thereby effecting electron transfer. For now we will only consider predicting the concentrations of ions in solutions of strong electrolytes. Ideally the end point and the equivalence point should be the same, but in most real situations there is a small difference between the two, which introduces a small error into the measurement. Thus, oxidation numbers are Cl = -1, H = +1 Notice that oxidation numbers are written as +1 vs. 1+ to distinguish them from charges.