Reaction Answers

Home Pre AP/IB Chem AP/IB Chem IB Chem Chem Online

ANSWERS TO PREDICTING EQUATIONS

1. Na2SO3 + H2O à Na+ + HSO3- + OH- soluble salt forms a weak base SO3- ( anion from weak acids) Hydrolysis

2. Cr2O7 + Pb2+ à PbCr2O7 double displacement forms precipitant

3. CaCO3 + H+ à Ca2+ + CO2 + H2O double displacement gas forming carbonic acid decomposes in water to form water and carbon dioxide

4. Cd2+ + H2S à CdS + H+ displacement forming a precipitant

5. HC2H3O2 + HCO3- à C2H3O2- + CO2 + H2O displacement acid- base

6. HCl + H2O à H3O+ + Cl- displacement acid-base

7. CO2 + H2O + NH3 à NH4+ + HCO3- carbonic acid in water write carbon dioxide and water displacement acid-base

8. Li2O + H2O à Li+ + OH- metal oxides and water form metallic hydroxides combination

9. SO3 + OH- à HSO4- combination nonmetal oxide and water form nonbinary acids

10. CaO + P4O10 à Ca3(PO4)2 combination metal oxide and nonmetal oxide forms nonbinary salt

11. MgCO3 à MgO + CO2 decomposition

12. PCl3 + H2O à H+ + Cl- + H3PO3 hydrolysis does not fit pattern exactly

13. NaCN + H2O à HCN + Na+ + OH- hydrolysis CN- is a base because it is an cation from a weak acid

14. Zn(NO3)2 + OH- à Zn(OH)42- + NO3- formation of complex ion ~ key words "excess sodium hydroxide"

15. Ag(NH3)+ + Cl- + H+ à AgCl + NH4+ breakup of complex ion achieved by adding an acid that reacts with the basic ligand

16. Cu(OH)2 + NH3 à Cu(NH3)42+ + OH- formation of complex ion ~ key word "excess ammonia"

17. BH3 + NH3 à BH3NH3 Lewis acid base ~ coordinate covalent bond

18. BF3 + (CH3)3N à F3BN(CH3)3 Lewis acid base ~ coordinate covalent bond

19. SiH4 + O2 à SiO2 + H2O combustion forms oxides of elements

20. Mg + N2 à Mg3N2 synthesis, combination

21. H2O2 + H+ + I- à H2O + I2  redox

22. MnO4- + H+ + H2C2O4 à Mn2+ + CO2 +H2O  redox

23. Sn2+ + H+ Cr2O72- à Sn4+ + Cr3+ + H2O redox remember to add H2O to have H’s and O's on both sides of the equation

24. Cu + H+ + NO3- à Cu2+ + NO + H2O redox

25. Cr2O7 2- + H+ + I- à Cr3+ + I2 + H2O redox

26. NaH + HOH à Na+ + OH- + H2 metal hydrides react with water to form metallic hydroxides and hydrogen

27. Fe + Fe3+ à Fe2+ redox intermediate ox state

28. Cl2 + Br- à Cl- + Br2 single displacement nonmetal displaces nonmetal

29. Na + HOH à Na+ + OH- + H2 single displacement metal displaces metal

30. H2O à H2 + O2 electrolysis