oxidising & reducing agents

oxidising & reducing agents

source : slide player.com

Oxidising agents or oxidants : are substances which

  • Show gain of electrons
  • Oxidise other substances
  • are reduced themselves
  • Show a decrease in oxidation no.

Reducing Agents or Reductants : are substances which

  • Show loss of electrons
  • reduce other substances
  • are oxidised themselves
  • show an increase in oxidation no.

Redox reaction is a process in which reducing agent is oxidised & liberate electrons, which are then taken up by an oxidising agent to get itself reduced. In redox rxns oxidation and reduction occur simultaneously.

Ex.

  • Identify the oxidizing agent and the reducing agent in the following redox reaction:
    MnO2(s)+4H+(aq)+2Cl(aq)Mn2+(aq)+2H2O(l)+Cl2(g)

 

  • Cl

is the reducing agent because it is oxidized and loses one electron (starting with an oxidation state of -1 in the Cl ions and increasing to 0 in Cl2). Remember that gaining electrons means it is “reduced”.  MnO2 is the oxidizing agent because it is reduced by gaining two electrons (starting with Mn in an oxidation state of +4 in MnO2 and decreasing to +2 in free Mn2+

  • ions). Keep in mind that losing electrons means it is “oxidized”.