Balancing Chemical Equations

CA Standards Students know how to describe chemical reactions by writing balanced equations.

Law of Conservation of Mass In ordinary chemical reactions, the total mass of reacting substances is equal to the total mass of products – All atoms on the reactant side must appear on the product side, and in equal numbers – No new elements may appear – No elements may disappear In ordinary chemical reactions, the total mass of reacting substances is equal to the total mass of products – All atoms on the reactant side must appear on the product side, and in equal numbers – No new elements may appear – No elements may disappear

Synthesis Reactions 1. ___CaO + ___H 2 O  ___Ca(OH) 2 2. ___P 4 + ___O 2  ___P 2 O 5 3. ___Ca + ___O 2  ___CaO 4. ___Cu + ___S 8  ___ CuS 5.___CaO + ___H 2 O  ___Ca(OH) 2 6. ___S 8 + ___O 2  ___SO 2 7.___H 2 + ___N 2  ___NH 3 8.___H 2 + ___Cl 2  ___HCl 9.___Ag + ___S 8  ___Ag 2 S 10.___Cr + ___O 2  ___Cr 2 O 3 11.___Al + ___Br 2  ___AlBr 3 12.___Na + ___I 2  ___NaI 13.___H 2 + ___O 2  ___H 2 O 14. ___Al + ___O 2  ___Al 2 O 3

Decomposition Reactions 15. ___BaCO 3  ___BaO + ___CO 2 16.___MgCO 3  ___MgO + ___CO 2 17.___K 2 CO 3  ___K 2 O + ___CO ___Zn(OH) 2  ___ZnO + ___H 2 O 19. ___Fe(OH) 2  ___FeO + ___H 2 O 20. ___Ni(ClO 3 ) 2  ___NiCl 2 + ___O ___NaClO 3  ___NaCl + ___O ___KClO 3  ___KCl + ___O ___H 2 SO 4  ___H 2 O + ___SO ___H 2 CO 3  ___H 2 O + ___CO ___Al 2 O 3  ___Al + ___O ___Ag 2 O  ___Ag + ___O 2

Decomposition Reactions 15. ___BaCO 3  ___BaO + ___CO 2 16.___MgCO 3  ___MgO + ___CO 2 17.___K 2 CO 3  ___K 2 O + ___CO ___Zn(OH) 2  ___ZnO + ___H 2 O 19. ___Fe(OH) 2  ___FeO + ___H 2 O 20. ___Ni(ClO 3 ) 2  ___NiCl 2 + ___O ___NaClO 3  ___NaCl + ___O ___KClO 3  ___KCl + ___O ___H 2 SO 4  ___H 2 O + ___SO ___H 2 CO 3  ___H 2 O + ___CO ___Al 2 O 3  ___Al + ___O ___Ag 2 O  ___Ag + ___O 2

Single Replacement Reactions 27. ___AgNO 3 + ___Ni  ___Ni(NO 3 ) 2 + ___Ag 28. ___AlBr 3 + ___Cl 2  ___AlCl 3 + ___Br ___NaI + ___Br 2  ___NaBr + ___I ___Ca + ___HCl  ___CaCl 2 + ___H ___Mg + ___HNO 3  ___Mg(NO 3 ) 2 + ___H ___ Zn + ___H 2 SO 4  ___ZnSO 4 + ___H ___K + ___H 2 O  ___KOH + ___H ___Na + ___H 2 O  ___NaOH + ___H 2

Double Replacement Reactions 35. ___AlI 3 + ___HgCl 2  ____AlCl 3 + ____HgI 2 (ppt) 36. ___HCl + ___NaOH  ___NaCl ___H 2 O 37. ___BaCl 2 + ___H 2 SO 4  ___BaSO 4 + ___HCl 38. ___Al 2 (SO 4 ) 3 + ___Ca(OH) 2  ___Al(OH) 3 + ___CaSO ___AgNO 3 + ___K 3 PO 4  ___Ag 3 PO 4 + ___KNO ___CuBr 2 + ___AlCl 3  ___CuCl 2 + ___AlBr ___Ca(C 2 H 3 O 2 ) 2 + ___Na 2 CO 3  ___CaCO 3 + ___NaC 2 H 3 O ___NH 4 Cl + ___Hg 2 (C 2 H 3 O 2 ) 2  ___NH 4 C 2 H 3 O 2 + ___Hg 2 Cl ___Ca(NO 3 ) 2 + ___HCl  ___CaCl 2 + ___HNO ___FeS + ___HCl  ___FeCl 2 + ___H 2 S 45. ___Cu(OH) 2 + ___HC 2 H 3 O 2  ___Cu(C 2 H 3 O 2 ) 2 + ___H 2 O 46. ___Ca(OH) 2 + ___H 3 PO 4  ___Ca 3 (PO 4 ) 2 + ___H 2 O 47. ___CaBr 2 + ___KOH  ___Ca(OH) 2 + ___KBr

Combustion Reactions 48. ___CH 4 + ___O 2  ___CO 2 + ___H 2 O 49. ___C 2 H 6 + ___O 2  ___CO 2 + ___H 2 O 50. ___C 3 H 8 + ___O 2  ___CO 2 + ___H 2 O 51. ___C 4 H 10 + ___O 2  ___CO 2 + ___H 2 O 52. ___C 5 H 12 + ___O 2  ___CO 2 + ___H 2 O 53. ___C 6 H 14 + ___O 2  ___CO 2 + ___H 2 O 54. ___C 2 H 4 + ___O 2  ___CO 2 + ___H 2 O 55. ___C 2 H 2 + ___O 2  ___CO 2 + ___H 2 O 56. ___C 6 H 6 + ___O 2  ___CO 2 + ___H 2 O