1 / 20

Chapter 7: Reactions in Aqueous Solutions

Chapter 7: Reactions in Aqueous Solutions. Will Learn About. (1) Driving forces behind chemical reactions (2) 3 Ways to write chemical reactions in aqueous solutions (3) Acid – bases Reactions (4) Oxidation – reduction reactions ( Redox ) (5) Classification of chemical reactions.

meghan
Download Presentation

Chapter 7: Reactions in Aqueous Solutions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 7: Reactions in Aqueous Solutions

  2. Will Learn About (1) Driving forces behind chemical reactions (2) 3 Ways to write chemical reactions in aqueous solutions (3) Acid – bases Reactions (4) Oxidation – reduction reactions (Redox) (5) Classification of chemical reactions

  3. Four Driving Forces Favor Chemical Change • Formation of a solid= precipitation • Formation of water = acid-base reaction • Transfer of electrons = oxidation-reduction reaction • Formation of a gas

  4. Precipitation Reactions • Formation of solid product(s) from ions • solution with 100% ions = strong electrolyte (conduct electricity well) • solution with less than 100% but more than 0% ions = weak electrolyte (conduct electricity somewhat) • solution with 0% ions = nonelectrolyte (conduct no electricity)

  5. Solubility Rules • Deciding if soluble or insoluble product will form • When the rules contradict, go with the soluble (Ex) Na2CO3 soluble b/c all Na+ soluble

  6. Examples • Soluble or insoluble? 1) NaNO3 (aq) 2) CaSO4 (aq) 3) AgCl (aq) 4) KOH (aq) 5) Pb(OH)2 (aq)

  7. Writing Chem Equations of Aqueous Reactions • Molecular equation: Write all reactants and products as insoluble formula units 2) Ionic equation: Write soluble compounds as ions and insoluble compounds as formula units 3) Net-ionic equation: Remove the spectator ions from the ionic equation

  8. Molecular Equations (Ex) Mg(NO3)2+ 2NaOH  2NaNO3 + Mg(OH)2 (Ex) K2SO4 + 2HCl  2KCl + H2SO4

  9. Ionic Equations Molecular: Mg(NO3)2 + 2NaOH  2NaNO3 + Mg(OH)2 Ionic: Mg2+ + 2NO3– + 2Na+ + 2OH–  2Na+ + 2NO3– + Mg(OH)2 Molecular: K2SO4 + 2HCl  2KCl + H2SO4 Ionic: 2K+ + SO42 + 2H+ + 2Cl–  2K+ + SO42 + 2H+ + 2Cl–

  10. Net Ionic Equations Molecular: Mg(NO3)2 + 2NaOH  2NaNO3 + Mg(OH)2 Ionic: Mg2+ + 2NO3– + 2Na+ + 2OH–  2Na+ + 2NO3– + Mg(OH)2 Net ionic:Mg2++ 2OH–  Mg(OH)2 Molecular: K2SO4 + 2HCl  2KCl + H2SO4 Ionic: 2K+ + SO42 + 2H+ + 2Cl–  2K+ + SO42 + 2H+ + 2Cl– Net ionic: 2K+ + SO42 + 2H+ + 2Cl–  No reaction

  11. Example A sodium phosphate solution reacts with a lead(II) nitrate solution. What precipitate, if any, will form? • Write the molecular equation. • Write the ionic equation. • Write the net ionic equation.

  12. Acid-Base Reaction • Acids: contain H+ ions • Strong acids form strong electrolytes: HCl, HBr, HI, HNO3, H2SO4, HClO3, HClO4 • Weak acids form weak electrolytes • Nonmetal dissolved in water  acidic solution (Ex) SO2 + H2O  H2SO3 • Bases: contain OH–ions • Strong bases form strong electrolytes: 1A + OH, Ba(OH)2, Ca(OH)2, Sr(OH)2 • Acid-base reaction requires at least one strong • Weak acid and weak base don’t produce products • Always two products: water and salt • Metal dissolved in water  basic solution (Ex) 2Na + 2H2O  H2 + 2NaOH

  13. Oxidation-Reduction Reaction(RedoxRxn) • A reaction that involves a transfer of electrons. • 2Mg(s) + O2(g) 2MgO(s)

  14. Types of Reactions • Why need to know the type of reaction? • Help you figure out the products • Types of reactions • combustion • synthesis • decomposition • single displacement • double displacement • acid-base reaction • Oxidation-reduction

  15. Types of Chemical Reaction 1. Combustion Reaction a) Called as burning b) Combining with oxygen gas c) Combustion of hydrocarbon compoundsproduce CO2 and H2O. (Ex) 2CH3OH + 3O2 2CO2 + 4H2O d) Combustion of elements form binary oxide compounds (Ex) 4Fe + 3O2  2Fe2O3 N2+ 2O2 2NO2

  16. 2. Synthesis (Combination) a) Two or more elements or compounds combine to form a single compound. b) Combustion of elements is also synthesis. (Ex) 4Al + 3O2 2Al2O3 (Ex) 2K + Cl2  2KCl

  17. 3. Decomposition a) The exact opposite process of synthesis b) A compound decomposes to elements or simpler compounds (Ex) 2NaCl  2Na + Cl2 (Ex) CaCO3  CaO + CO2

  18. 4. Single Displacement • An element displaces a similar element in a compound; metal replaces metal (cationic)and nonmetal replaces nonmetal (anionic). • The element displaces less reactive element in the compound. *If the element in the compound is more reactive, no reaction occurs (Ex) 2NaCl + F2 2NaF + Cl2

  19. 5. Double Displacement a) Two compounds react and produce two different compounds b) Swap the cationsOR the anions – Do not swap both cations and anions (Ex) 2KBr + CaO CaBr2 + K2O

More Related