Investigate the Kinetics of a Common Inorganic Reaction

Planning (a):

Aim:

In this experiment, we are going to investigate the reaction between NaOH and HCl. The aim of the experiment is to find the rate equation for the reaction.

The rate equation has the general form:

Rate = k[NaOH]x[HCl]y

Rate : Speed of the reaction

k : Rate constant

[NaOH]x : NaOH raised to the power of x. The value for x can only be determined experimentally and is referred to as “the order of reaction with respect toвЂ¦Ð²Ð‚Ñœ, in this case, potassium permanganate.

[HCl]y : HCl concentration raised to some power y. Same criteria as those addressed for the potassium permanganate.

Method of Initial Rates:

In order to determine the speed of the reaction we are going to focus on the permanganate and simply equate the speed with the time it takes to use up the permanganate.

Rate = -в?†[NaOH]/ в?†t

= -{[HCl] final - [NaOH] initial}/(tfinal вЂ" tinitial)

[NaOH] final = 0, and tinitial = 0

Rate = -(-[NaOH] initial/tfinal)

= [NaOH]/t

We can use the method of initial rates to find the exponents x and y. This method involves measuring and comparing the initial rates of a reaction when different initial concentrations are used. The initial rate for each being the potassium permanganate concentration divided by time, there is an inherent assumption made that is not always valid. We will be measuring t (final) to determine each rate. Through the 3 different experiments, the data collected can be used to calculate the values of x, y and k.

Hypothesis:

The rate of reaction increased as the concentration of NaOH increased.

Planning (b):

Apparatus:

3 x 100cm3 burette

3 x 50cm3 beakers

1 x 150cm3 conical flask

1 x Stopwatch

~0.02M NaOH

~0.5M HCl

Distilled water