Kinetics of the Depolymerization of Diacetone Alcohol
Experiment N | Kinetics of the Depolymerization of Diacetone Alcohol via Basic Catalysis | | Ingrid Tafur -5672578 | 2/11/2011 |
CHM233O
Partner: Laura Marrongelli
Demonstrator: Cheryl McDowall
Objective
The rate constant of the depolymerization of diacetone alcohol via basic catalysis was determined by monitoring the change in volume as a function of time at constant temperature of a pseudo first order reaction where the species in excess was sodium hydroxide. This was accomplished by using a dilatometer as the apparatus and following both methods: isolation and initial rates in conjunction.
Introduction
Depolymerization is the process in which a compound is converted into one of a smaller molecular weight and of different physical properties, without changing the percentage relations of the elements composing it. The depolymerization or simply, the decomposition of diacetone alcohol into acetone molecules takes place via basic catalysis. The catalyst is capable of directing and accelerating thermodynamically the reaction while remaining unaltered at the end of the reaction. Diacetone alcohol is catalyzed by the hydroxide ions.
The reaction rate of a chemical reaction is the rate of decrease of the concentration of a reactant or the rate of increase of the concentration of a product. The rate law is an equation that expresses the rate of a reaction as a function of the concentration of all the species present in the overall chemical reaction at some time. The rate law is often found to be proportional to the concentration of the reactants raised to a power. For the depolymerization of diacetone alcohol the empirical rate equation is
-∂x∂t=kxn[OH-]m (1)
X= concentration of diacetone alcohol , t=time , k=rate constant, n+m= order of the reaction
Where concentration is in moles per litre, time is in seconds and the dimensions for k depend on the overall reaction order. The rate constant ‘k’ is independent of the concentrations but
CHM233O
Partner: Laura Marrongelli
Demonstrator: Cheryl McDowall
Objective
The rate constant of the depolymerization of diacetone alcohol via basic catalysis was determined by monitoring the change in volume as a function of time at constant temperature of a pseudo first order reaction where the species in excess was sodium hydroxide. This was accomplished by using a dilatometer as the apparatus and following both methods: isolation and initial rates in conjunction.
Introduction
Depolymerization is the process in which a compound is converted into one of a smaller molecular weight and of different physical properties, without changing the percentage relations of the elements composing it. The depolymerization or simply, the decomposition of diacetone alcohol into acetone molecules takes place via basic catalysis. The catalyst is capable of directing and accelerating thermodynamically the reaction while remaining unaltered at the end of the reaction. Diacetone alcohol is catalyzed by the hydroxide ions.
The reaction rate of a chemical reaction is the rate of decrease of the concentration of a reactant or the rate of increase of the concentration of a product. The rate law is an equation that expresses the rate of a reaction as a function of the concentration of all the species present in the overall chemical reaction at some time. The rate law is often found to be proportional to the concentration of the reactants raised to a power. For the depolymerization of diacetone alcohol the empirical rate equation is
-∂x∂t=kxn[OH-]m (1)
X= concentration of diacetone alcohol , t=time , k=rate constant, n+m= order of the reaction
Where concentration is in moles per litre, time is in seconds and the dimensions for k depend on the overall reaction order. The rate constant ‘k’ is independent of the concentrations but