The Importance Of Clock Reaction

The experiment is to observe a variety of chemical reactions and to identify patterns in

A clock reaction is characterised by an abrupt colour change following an established time lag (Lente et al, 2007). The induction period in a clock reaction is a result of low concentrations of the clock chemical (i.e. the chemical that enables the final reaction). The induction period ends after the total consumption of a limiting reagent, which initiates a short increase in the rate of product formation, resulting in a visible colour change (Schmitz, 2010)(Lente et al, 2007). The reaction rate of clock reactions is subject to factors including temperature, concentration, catalysis and inhibition. These factors can be manipulated, thus changing the length of the induction period in a ‘clock-like’ manner (Shakhashiri, 1992).

The standard rate law for the Iodine Clock reaction, is a first order reaction for KIO3 and a second order reaction for NaHSO3. To determine this you must substitute the values into the equations and whichever produces a straight line graph determines whether it is a first or second order reaction. In graph 1. It shows that KIO3 is a second order reaction, this is due to the second order reaction graph being straighter than the first order graph. This meaning the reaction proceeds at a rate proportional to the square of the concentration,

Procedure: In this experiment, various chemicals were mixed together, to determine a reaction. Using two drops from chemical 1 and two drops of chemical two, unless otherwise stated, then recording the type of physical reaction or color changes that occurred.

Rate= k [I-]1[H2O2]. (2.13675*10-5 ) = k [0.015] [0.015] then solve for k. For this trial, k=0.09497.

9. Discared the solutions. The next step is to analyze the data graphically to see if the reaction is zero, 1st or 2nd order with respect to crystal violet. The reaction is

In this experiment we tested the effects that enzymes and substrate have on chemical reaction rates, which is the rate at which chemical reactions occur.. This experiment tested how different concentrations of enzyme and substrate affected the light absorption measurements on a spectrophotometer. The experiment also tested how temperature affected the light absorption, and in a separate test, the effect of the enzyme inhibitor hydroxylamine was also tested. In the first test conducted, 3 different concentrations of enzyme, and three different concentrations of substrate were measured in a spectrophotometer. For the enzyme and the substrate, the measurements got higher as the concentrations were higher, but the over measurements of the substrate were smaller than those of the enzyme. In the second test conducted, the medium concentration enzyme was tested under the temperatures; 4°C, 23°C, 37°C, and 60°C. The measurements in this test got higher as the temperature got higher, but did the measurements under 4°C were overall significantly higher than the other temperature measurements. Lastly, the last test conducted showed that the measurements of the substance with 0 and 1 drop of hydroxylamine inhibitor went up, but the measurements of the enzyme with 5 drops of hydroxylamine inhibitor stayed rather low and did not change much. In conclusion, these experiments showed that chemical reaction rates are sped up with higher concentrations of enzyme, substrate,

When Zinc Chloride was mixed with water, the solution was first green and when stirred turned light blue

Soon they change from red to orange and then to yellow! After the yellow stage, they finish off as a green color. Once your solution has turned to a green color, you know that the chemical reaction is complete! This is a large money saver for people that want to know when chemical reactions are complete so they don't have to do additional testing.

The reaction turned from blue to a blotchy bowl of blue, green, and yellow. Similar to oil not mixing with water, the

The purpose of this experiment was to investigate the stoichiometric relationship between reactants and products in two different reactions.

The point at which the indicator changes colour is called the end point. A suitable indicator should be chosen, preferably one that will experience a change in colour (an end point) close to the equivalence point of the reaction.

This color change is indicated by the equation

Kinetics of chemical reactions is how fast a reaction occurs and determining how the presence of reactants affects reaction rates. In this experiment the rate of reaction for Fe+3 and I- is determined. Because the rate of chemical reactions relates directly to concentration of reactants, the rate law is used to find the rate constant, and calculated with specified temperatures.

The key aim of this experiment was to determine the rate equation for the acid-catalysed iodination of acetone and to hence consider the insinuations of the mechanism of the rate equation obtained.