State the Oxidation Number of each of the elements that is underlined.
a) NH3 _____ b) H2SO4 _____
c) ZnSO3 _____ d) Al(OH)3 _____
a) NH3: The oxidation number of hydrogen in most compounds is +1. Therefore, each hydrogen atom in NH3 will have an oxidation number of +1. The oxidation number of nitrogen in compounds is typically -3. Therefore, the oxidation number of nitrogen in NH3 will be -3.
b) H2SO4: The oxidation number of hydrogen in most compounds is +1. Therefore, each hydrogen atom in H2SO4 will have an oxidation number of +1. The oxidation number of sulfur in compounds is typically +6. Therefore, the oxidation number of sulfur in H2SO4 will be +6. The oxidation number of oxygen in compounds is typically -2. Since there are four oxygen atoms in H2SO4, the total oxidation number for oxygen will be -8. Therefore, the oxidation number of sulfur in H2SO4 can be determined by the following equation: 2*(+1) + x + 4*(-2) = 0. Solving this equation, we find that x (the unknown oxidation number) is equal to +6.
c) ZnSO3: The oxidation number of zinc in most compounds is +2. Therefore, the oxidation number of zinc in ZnSO3 will be +2. The oxidation number of sulfur in compounds is typically +6. Therefore, the oxidation number of sulfur in ZnSO3 will be +6. The oxidation number of oxygen in compounds is typically -2. Since there three oxygen atoms in ZnSO3, the total oxidation number for oxygen will be -6. Therefore, the oxidation number of zinc in ZnSO3 can be determined by the following equation: x + 3*(-2) = 0. Solving this equation, we find that x (the unknown oxidation number) is equal to +6.
d) Al(OH)3: The oxidation number of hydrogen in most compounds is +1. Therefore, each hydrogen atom in Al(OH)3 will have an oxidation number of +1. The oxidation number of aluminum in most compounds is +3. Therefore, the oxidation number of aluminum in Al(OH)3 will be +3. The oxidation number of oxygen in compounds is typically -2. Since there are three oxygen atoms in Al(OH)3, the total oxidation number for oxygen will be -6. Therefore, the oxidation number of aluminum in Al(OH)3 can be determined by the following equation: 3*(+1) + x + 3*(-2) = 0. Solving this equation, we find that x (the unknown oxidation number) is equal to +3.