Calculate DG and Kc for the following reactions at 25C: (a) Mg(s) 1 Pb21(aq) Mg21(aq) 1 Pb(s) (b) Br2(l) 1 2I2(aq) 2Br2(aq) 1 I2(s) (c) O2(g2 1 4H1(aq) 1 4Fe21(aq) 2H2O(l) 1 4Fe31(aq) (d) 2Al(s) 1 3I2(s) 2Al31(aq) 1 6I2(aq)
Chemical Reactions reactants products gas (g) liquid (l) solid (s) aqueous (aq) Examples: Burning methane (CH )4in oxygen produces carbon dioxide and water. CH + O CO + H O 4(g) 2(g) 2(g) 2 (g) unbalanced reaction -includes each substance but not in a particular ratio Balancing Equations Unbalanced : CH 4(g) + O 2(g) CO + H2O (g) 2(g) Balanced : CH 4(g) + 2O 2(g) CO 2(g)+ 2H 2 (g) Coefficient a balanced equation has the same number of each -indicates the # of atom on either side of the equation (i.e. 2 Oxygen and 4 Hydrogen on either side) each kind of molecule Unbalanced: C 3 +8O 2 CO + H O 2 2 Balanced: C3H 8 5 O 2 3 CO + 4 H O 2 2 Unbalanced : CH 4O +CO 2 2+ H2O Balancing : 2(CH 4 + O (3/C)O 2 2+ 2H 2 ) 1 O + 3 O 4 O 1 C