It is a popping resonating sound generated by a lean condition on deceleration. When you suddenly close the throttle, the incoming air is choked off and the closed throttle also causes the bike to return to idle on the very lean idle circuit.
The reactivity series of metals was deduced by performing several experiments in the lab which enabled scientists to arrange metals according to their reactivity with dilute acid, oxygen (air), and water.xides of iron and copper are insoluble. Metals that are less reactive than copper like silver, gold and platinum do not react with oxygen. Note: When aluminum reacts with oxygen, a layer of aluminum oxide adheres and covers the aluminum.
2 Al(s) + Fe2O3(s) Al2O3(s) + 2 Fe(l). By assigning oxidation numbers, we can pick out the oxidation and reduction halves of the reaction. Aluminum is oxidized to Al 2 O 3 in this reaction, which means that Fe 2 O 3 must be the oxidizing agent.Conversely, Fe 2 O 3 is reduced to iron metal, which means that aluminum must be the reducing agent.Because a reducing agent is always transformed into its conjugate oxidizing agent in an oxidation-reduction reaction, the products of this reaction include a new oxidizing agent (Al 2 O 3) and a new reducing agent (Fe).n the course of this reaction, CuO is reduced to copper metal. Thus, H 2 is the reducing agent in this reaction, and CuO acts as an oxidizing agent. An important feature of oxidation-reduction reactions can be recognized by examining what happens to the copper in this pair of reactions.