 We know that the group 14 elements commonly exist in two oxidation states one is plus 4 and the other one is plus 2 and not just that. Some of these elements are more stable in one particular oxidation state than the other. So in this video we are going to see how this difference in the stability of these oxidation states can help us figure out which of these elements can act as an oxidizing agent and which of them can act as a reducing agent. For example if you take lead we know that lead is more stable in plus 2 oxidation state rather than in plus 4 due to inert per effect right. That means a compound of lead in plus 4 oxidation state would want to move to a more stable plus 2 oxidation state right and in this process it would have to gain electrons or act as an oxidizing agent in the process. So let's understand this better with an example. So here we have lead oxide reacting with hydrochloric acid to form lead chloride, PbCl2, Cl2 and water. Now what is the oxidation state of lead in the reactant and the product side? So in this reaction the oxidation state of lead changes from plus 4 to plus 2 and what about chlorine? Well chlorine changes from minus 1 to 0 right. So that means lead undergoes reduction and in the process oxidizes chlorine. Now the driving force for this reaction is the formation of a more stable state especially for lead. As you can see lead has gone from the less stable plus 4 oxidation state to the more stable plus 2 oxidation state and on doing so lead in plus 4 acts as an oxidizing agent. So let's now look at another reaction. In this reaction tin chloride is reacting with ferric chloride to form SNCl4 and FeCl2. So let's quickly figure out the oxidation states of our group 14 element here okay. So what is it? Here in the reactant side tin has plus 2 oxidation state while it gets plus 4 oxidation state in the product and what about iron? We can see that iron changes its oxidation from plus 3 to plus 2. So what is exactly happening here? As the oxidation state of tin increases from plus 2 to plus 4 it is undergoing oxidation and in the process it reduces iron from plus 3 to plus 2 oxidation state. So that means tin in plus 2 oxidation state will act as a reducing agent. Now remember folks we already know that plus 2 and plus 4 oxidation states are quite common for tin red. I mean we can find a lot of compounds in these oxidation states. However tin is much more stable in the plus 4 oxidation state and this is why it is fairly easy to convert tin compounds from plus 2 to plus 4. And precisely the reason why SN2 plus ions in solutions are strong reducing agents. As you can see depending on the stability of the oxidation states the group 14 elements can act as an oxidizing or a reducing agent in a particular reaction. Let's now solve a question to see if you really understood what we have been talking about so far ok. So the question is would carbon monoxide most likely act as an oxidizing agent or a reducing agent in a particular reaction. So pause the video here take a moment and think about it. Alright so how do we solve this? Well firstly to figure out if carbon monoxide acts as an oxidizing or a reducing agent we first need to find out its oxidation state right oxidation state of carbon in particular. And then we will see if it can attain a more stable state by gaining or losing electrons. If it attains a more stable state by gaining electron then it acts as an oxidizing agent and if it attains stability by losing electrons then it acts as a reducing agent right. Now in carbon monoxide the oxidation state of carbon is plus 2 and that of oxygen would be yes you are right minus 2. But we know that the more stable oxidation state of carbon is plus 4. So to move from the less stable plus 2 to the more stable plus 4 oxidation state it needs to lose electrons in other words undergo oxidation and in doing so what is it acting as? Yes a reducing agent. In fact carbon monoxide is one of the strongest reducing agents and as we will learn later in metallurgy one of the important commercial applications of carbon monoxide or the reducing property of carbon monoxide is in the blast furnace in the extraction of iron. So to summarize we saw two reactions of the group 14 elements one in which the element changes from plus 4 to plus 2 oxidation state and thereby acts as an oxidizing agent and another reaction in which it goes from plus 2 to plus 4 oxidation state and thereby acts as a reducing agent. Now as I have mentioned repeatedly in this video this change can happen only if the element attains a more stable oxidation state. So if I ask you what is the order of the oxidizing nature of the group 14 elements what would you answer me? Well that depends on the stability of the plus 2 oxidation state right and we know that the stability of the plus 2 oxidation state is in the order lead greater than tin greater than germanium greater than silicon greater than of course carbon. So that means the oxidizing nature of the group 14 elements would also be in the same order where lead would be most oxidizing and carbon would be the poorest oxidizing agent. In other words lead would have the maximum tendency to attain the plus 2 oxidation state whereas carbon would have the least tendency. On extending this what would be the correct order of the reducing nature of the group 14 elements? Well that again depends on the stability of the plus 4 oxidation state right and stability of plus 4 oxidation state decreases down the group. That means the reducing nature of these elements would also be in the same order that is carbon would have the maximum tendency to go from plus 2 to plus 4 oxidation state whereas lead would have the least tendency to move to plus 4 oxidation state.