The aim of this experiment is to find out how different temperatures of hydrogen peroxide and catalyse will affect the volume of oxygen produced.
#Chemistry Coursework
Title:
An experiment to measure the volume of oxygen produced with Hydrogen Peroxide and Celery Catalyse reacting at varying temperatures.
Aim:
The aim of this experiment is to find out how different temperatures of hydrogen peroxide and catalyse will affect the volume of oxygen produced.
Diagram
Variables:
Independent Variable: Temperature
Dependant Variable: Volume of Oxygen produced.
Control Variables: Light, concentration, volume of hydrogen peroxide and catalyse solution, apparatus, pH,
To ensure this experiment is carried out fairly we will use sensible measuring cylinders (i.e. if the measurement is 10cm3 then we will use a 10cm3 cylinder). Also we will use the same person for timing and measuring this will accuracy. A control I will carry out is by doing my experiment at room temperature.
Prediction
I predict that the more catalyse used will speed up the reaction rate between the catalyse and hydrogen peroxide. On a graph, as the temperature of hydrogen peroxide and the catalyse is increased the rate of reaction will increase forming a series of positively correlated lines, increasing in gradient as the hydrogen peroxide and the catalyse temperature increases. The optimum temperature will be about 35°C. On a graph, the rate of reaction will be directly proportional to the temperature of each hydrogen peroxide and catalyse sample, producing a positively correlated scatter graph with a line of best fit, however after a certain temperature about 40°C the enzymes will denature and the rate of reaction will slow down and soon stop this. The particular enzymes in question are breaking enzymes and they will engulf the substrate and separate it into smaller pieces and release it. The enzymes will not die or be used up and will continue working until all the substrate is reacted with.
Predicted Graph
Justification of prediction
The lock and key hypothesis
Enzymes are biological catalysts usually a protein made in living cells. This means that they speed up the chemical reactions in living things. Enzymes are large molecules with hundreds of amino acids. Only a small part of the enzyme participates in the reactions, this is called the active site. The three-dimensional structure of the enzyme determines the appearance of the active site. The active site accommodates the shape of the substrate that requires transformation. This is what makes enzymes specific in their actions. Only substances of the right shape will be transformed.
The lock and key theory is about how enzymes work. The job of the enzyme is as follows:
First the enzyme 'finds' the substrate and they join. The product is called an enzyme substrate complex.
Secondly the enzyme 'tweaks' the substrate and the products leave the active site. As the enzyme is a catalyst it remains unchanged and can do the same to another substrate molecule.
Temperature is the main factor that affects enzymes and enzyme activity. If the temperature is increased the molecules move faster. More meetings occur so the rate of the reaction increases. At high temperatures the enzymes begin to become denatured, in the human body this happens between 40 - 60°C. Also very acidic or very alkaline conditions also denature enzymes. Poisons like lead and mercury can denature enzymes and making them stop working. Reason being that enzymes are proteins and their structure is 3D and increasing the temperature disturbs the inner molecules that make the shape of the enzyme. A substrate cannot fit into a denatured enzyme hence it is useless.
The Collision Theory
The collision theory explains that the rate of reaction depends on how often and how hard the reacting particles collide with each other. This is because particles have to collide in order to react; they also have to collide hard enough. There are four main methods of increasing the rate of reaction.
Title:
An experiment to measure the volume of oxygen produced with Hydrogen Peroxide and Celery Catalyse reacting at varying temperatures.
Aim:
The aim of this experiment is to find out how different temperatures of hydrogen peroxide and catalyse will affect the volume of oxygen produced.
Diagram
Variables:
Independent Variable: Temperature
Dependant Variable: Volume of Oxygen produced.
Control Variables: Light, concentration, volume of hydrogen peroxide and catalyse solution, apparatus, pH,
To ensure this experiment is carried out fairly we will use sensible measuring cylinders (i.e. if the measurement is 10cm3 then we will use a 10cm3 cylinder). Also we will use the same person for timing and measuring this will accuracy. A control I will carry out is by doing my experiment at room temperature.
Prediction
I predict that the more catalyse used will speed up the reaction rate between the catalyse and hydrogen peroxide. On a graph, as the temperature of hydrogen peroxide and the catalyse is increased the rate of reaction will increase forming a series of positively correlated lines, increasing in gradient as the hydrogen peroxide and the catalyse temperature increases. The optimum temperature will be about 35°C. On a graph, the rate of reaction will be directly proportional to the temperature of each hydrogen peroxide and catalyse sample, producing a positively correlated scatter graph with a line of best fit, however after a certain temperature about 40°C the enzymes will denature and the rate of reaction will slow down and soon stop this. The particular enzymes in question are breaking enzymes and they will engulf the substrate and separate it into smaller pieces and release it. The enzymes will not die or be used up and will continue working until all the substrate is reacted with.
Predicted Graph
Justification of prediction
The lock and key hypothesis
Enzymes are biological catalysts usually a protein made in living cells. This means that they speed up the chemical reactions in living things. Enzymes are large molecules with hundreds of amino acids. Only a small part of the enzyme participates in the reactions, this is called the active site. The three-dimensional structure of the enzyme determines the appearance of the active site. The active site accommodates the shape of the substrate that requires transformation. This is what makes enzymes specific in their actions. Only substances of the right shape will be transformed.
The lock and key theory is about how enzymes work. The job of the enzyme is as follows:
First the enzyme 'finds' the substrate and they join. The product is called an enzyme substrate complex.
Secondly the enzyme 'tweaks' the substrate and the products leave the active site. As the enzyme is a catalyst it remains unchanged and can do the same to another substrate molecule.
Temperature is the main factor that affects enzymes and enzyme activity. If the temperature is increased the molecules move faster. More meetings occur so the rate of the reaction increases. At high temperatures the enzymes begin to become denatured, in the human body this happens between 40 - 60°C. Also very acidic or very alkaline conditions also denature enzymes. Poisons like lead and mercury can denature enzymes and making them stop working. Reason being that enzymes are proteins and their structure is 3D and increasing the temperature disturbs the inner molecules that make the shape of the enzyme. A substrate cannot fit into a denatured enzyme hence it is useless.
The Collision Theory
The collision theory explains that the rate of reaction depends on how often and how hard the reacting particles collide with each other. This is because particles have to collide in order to react; they also have to collide hard enough. There are four main methods of increasing the rate of reaction.
