Parallel or Competitive Reactions
When a substance reacts simultaneously to give two different products, a parallel or competitive reaction is said to take place.
- Two first order reactions:
and, with constants and and rate equations, and
The integrated rate equations are then ; and .
One important relationship in this case is
- One first order and one second order reaction:
This can be the case when studying a bimolecular reaction and a simultaneous hydrolysis (which can be treated as pseudo order one) takes place: the hydrolysis complicates the study of the reaction kinetics, because some reactant is being "spent" in a parallel reaction. For example A reacts with R to give our product C, but meanwhile the hydrolysis reaction takes away an amount of A to give B, a byproduct: and . The rate equations are: and . Where is the pseudo first order constant.
The integrated rate equation for the main product is, which is equivalent to . Concentration of B is related to that of C through
The integrated equations were analytically obtained but during the process it was assumed that therefeore, previous equation for can only be used for low concentrations of compared to 0
Read more about this topic: Rate Equation
Famous quotes containing the words parallel, competitive and/or reactions:
“As I look at the human story I see two stories. They run parallel and never meet. One is of people who live, as they can or must, the events that arrive; the other is of people who live, as they intend, the events they create.”
—Margaret Anderson (1886–1973)
“How deep is our desire to do better than our mothers—to bring daughters into adulthood strong and fierce yet loving and gentle, adventurous and competitive but still nurturing and friendly, sweet yet sharp. We know as working women that we can’t quite have it all, but that hasn’t stopped us from wanting it all for them.”
—Anne Roiphe (20th century)
“In this Journal, my pen is a delicate needle point, tracing out a graph of temperament so as to show its daily fluctuations: grave and gay, up and down, lamentation and revelry, self-love and self-disgust. You get here all my thoughts and opinions, always irresponsible and often contradictory or mutually exclusive, all my moods and vapours, all the varying reactions to environment of this jelly which is I.”
—W.N.P. Barbellion (1889–1919)