Factors That Affect The Rate Of Catalytic Process

This website was used on October 3, 2014 to help develop a better understanding of collision theory in order to explain the various factors affecting the rate of reaction.

Used to see if the temperature of the water is at 37oc – 40oc and if

PURPOSE: Measure the effects of changes in catalase concentration, substrate concentration, and salinity on the reaction rates of an enzyme.

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,

Hypothesis: If the concentration of a substrate increases, any time an enzyme happens upon a substrate it will be free to help that substrate react, but then when an enzyme encounters a new substrate at a slightly higher concentration it will already be working on another substrate, therefore, as we increase substrate concentration it is not going to increase as fast as the reaction rate.

The Enzyme Properties Lab was performed to analyze the effects of pH, enzyme concentration, and temperature on the catalytic rate of enzymes. Many functions within the human body require/involve enzymes. It was found that enzymes have an optimal pH level, catalytic rate increases as the concentration of the enzyme increases, and an optimal temperature. The enzyme that was used throughout the experiment was ALP (alkaline phosphatase enzyme). ALP functions best at a neutral pH level, as it had the largest calculated enzyme activity of 2.05E-03. When pH went above or below the neutral value the enzyme activity tended to fall. ALP’s calculated enzyme activity tended to increase with an increase in enzyme concentration, as the calculated enzyme activity of the high enzyme concentration environment was 0.004607, which was larger than the other conditions. The last part of the experiment involved temperature and it was found that the optimal temperature for the enzyme was 32°C with a calculated enzyme activity of 0.000353. When temperature was below or above the optimal temperature the calculated enzyme activity dropped. Enzymes can begin to change shape and lose function when conditions are not appropriate, which was seen in the enzyme activity of ALP in varying environments. It can be concluded that enzymes play a major role in many reactions, but if conditions (pH, enzyme concentration, and temperature) are not appropriate enzyme activity tends to drop. The results supported the

Effects of Temperature Variation on the rate of Enzymatic Activity of Peroxidase Abstract In order to examine the effects of temperature on the enzyme peroxidase we measure amount of accumulated electron donor guaiacol, which turns brown when oxidized during the reaction of hydrogen peroxide and peroxidase, via a spectrophotometer at various temperatures. We measured two sets of temperature variations: one in which the reactions happened at various temperatures, and on in which the reactants were allowed to return to room temperature after this increase/decrease in temperature before reacting. We found that extremely cold and hot temperatures showed the least amount of absorption change, as well as the least amount of absorption change even once recovered back to room temperature due to the denaturing of peroxidase in these extreme temperatures.

A Catalyst is a substance that increases the rate of reaction by providing alternate routes for the reaction to take place/lowering the activation energy which is the minimum energy required for a reaction to happen. It does not undergo any change itself making it useful as it is recyclable and they reduce manufacturing costs. The 2 types of catalysts are heterogeneous catalysts and homogenous catalysts. Another substance, called the Inhibitor, does the opposite of a catalyst by reducing the rate of a reaction.

2) A small amount is required as the enzyme is used again and again as

To begin the lab, part A was performed to determine the amount of enzyme that would produce a reaction rate that did not proceed too slow or too rapidly. As seen on page 13 of the Lab Handout, varying amounts of tyrosinase and phosphate buffer were added to a cuvette while the amount of the L-DOPA was constant. After all reagents were added to the cuvette, the cuvette was inserted into spectrophotometer and absorbance of product formation at 475 nm was recorded for two minutes at fifteen seconds interval. After absorbance of product formation was measured and recorded for each cuvette, as shown on page 14 of the Lab Handout, graphs of rate of production formation versus time, were made with the data of each cuvettes and the

Catalysts are an extremely important part of the experiment, but to understand catalyst you first must understand Activation energy. Activation Energy is “the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo chemical transformation or physical transport.” (Encyclopedia Britannica, "activation energy | chemistry"). A Catalyst is “is a substance which speeds up a reaction, but is chemically unchanged at the end of the reaction. When the reaction has finished, you would have exactly the same mass of catalyst as you had at the beginning.” A catalyst provides an “alternate route” for a reaction, one which has lower activation energy, there for speeding up the reaction by requiring the reaction to need less energy to begin, but only in specific conditions will they work to their full potential. (Clark, "The effect of catalysts on rates of reaction") An enzyme is a “catalyst in living organisms, regulating the rate at which chemical reactions proceed without it being altered in the process”. Catalysts work optimally in certain PHs, and can be altered when in temperatures and PH levels that are different then what they are used to (http://www.britannica.com/science/enzyme). Acids and bases are both materials that can inhibit the efficiency of a catalyst in a reaction. Materials can be considered acids or bases depending on their

The data supports the hypothesis that an exponential relationship will be found between the change in temperature and the reaction rate, and that the highest temperature will have the fastest rate of reaction. The data also supports the hypothesis that as the concentration of Potassium Iodine increases so will the reaction rate, and vice versa for an increase in Sodium Thiosulphate concentration. The hypothesis that the Iron (II) ions will affect the reaction rate, and that the optimal amount will be about 0.1M of catalyst was partially supported.

Specific enzymes made up of proteins are used in biology to speed up a chemical reaction of any kind. Since a spontaneous chemical reaction can occur without help from any outside energy it could potentially prolong the reaction to where it becomes almost unnoticeable since it can take years for it to happen. For this reason, enzymes take action as a catalyst that speed up the reaction rate without completely being absorbed (Campbell et al., 2010). Enzymes are a form of regulation that allow for a through pathway in chemical reactions. It is able to perform as a catalyst by lowering the activation energy which is the energy required to drive the reactant to the top of the energy barrier allowing the downhill part to begin. An

The presence of catalyst will cause hydrogen peroxide to break down into water and oxygen. The increase in the pH of the substrate will cause the increase in the rate of reaction. It will optimize at pH 7 and will diminish/moderate after pH 9.

Michaelis – Menten and Lineweaver – Burke kinetics of polyphenol oxidase . Effect of substrate concentration concentration on the rate of reaction”