effects of substrate concentration on the activity of the enzyme catalase.
Investigate the effects of substrate concentration on the activity of the enzyme catalase. To explain this, catalase is an enzyme found in potato cells, catalase breaks down the substrate Hydrogen-Peroxide into water + oxygen. Hydrogen Peroxide itself is a waste product found in potatoes and other fruit + vegetables. When I do this I will see with different concentrations of the substrate and see how quick the enzyme catalase works on it. The four things that affect the rate at which the substrate and enzyme would react are as follow:- * Susceptibility of temperature change. * Susceptibility to PH changes. * Enzyme concentration. * Substrate concentration. Now I will explain each one of these in detail and how they can change the rate of reaction in many different ways. Susceptibility of temperature: - Chemical reactions can be speeded up by heating the reactants, this makes molecules speed up and have sufficient energy for more successful collisions. If the temperature is too high the enzyme would vibrate and it would denature because the active-site would change shape. Susceptibility of PH changes: - Enzymes can be denatured by changes in PH. This happens because the ionisation of the Amino acids changes, the Ionic bonds with stabilise the enzyme, that shape is broken so they are no longer stable. So you need the right PH for the ionic bonds to stay stable for the
The effetct of copper nitrate on the germination of mustard seeds.
The effetct of copper nitrate on the germination of mustard seeds. Aim The aim of the experiment is to investigate the effect of diferent concentrations of copper nitrate upon the growth of germinating mustard seeds. Introduction A seed is an embryo plant and contains within itself all the materials and energy to start off a new plant. germination is started by the rapid uptake of water by the seed resulting in a dramatic increase in mass. although copper is generally an environmental hazard to humans only in regions surrounding mine sites and smelters, it also causes significant crop losses when it accumulates in soil where it is used as a fungicide. plants prevent damage from excess accumulation of the essential nutrient copper by means of internal and root surface mechanisms. most of the functions of copper as a plant nutrient are based on the participation of enzymatically bound copper in redox reactions. some plants growing on mine spoil heaps, which have resistent strains to toxic metal, have caused the plants to have the ability to transport copper out of the cell into the cell wall, so that it has less effect on cell metabolism. these copper tolerant grasses have evolved due to selection pressuresbeing placed on the plants, which has inturn led those who are better adapted, copper tollerant, to survive providing them with a selective advantage. Prediction
The aim is to investigate if there is a link between the number of carbon atoms in a fuel and the amount of heat produced by that fuel.
Chemistry - Coursework Aim The aim is to investigate if there is a link between the number of carbon atoms in a fuel and the amount of heat produced by that fuel. Prediction I predict that the more carbon atoms that are in a fuel, the more heat the fuel will generate. Risk Assessment There are some safety precautions that will have to be taken when the experiment is carried out. These will be determined by the hazards that are in the room and hazards that could occur. These are: * Heatproof mat * Goggles * Tie tucked in shirt * Hair clipped back * The alcohol's are flammable so care must be taken with them * Equipment might get hot * There will be naked flames Equipment used and reasons ³ Calorimeter - this is used to hold water. This is used because it is non flammable so even when in close contacts with the fuels, it will not burn. ³ Tripod - this is used to keep calorimeter at a safe distance away from the fuels. ³ Heat proof mat - this is used so that the desk does not get burned or marked when the fuels are burning. ³ Thermometer - this is used to measure the temperature of the water, before and after the experiment. ³ Measuring cylinder - this was used to measure the 100ml of water that was needed for the experiment. ³ Alcohols - this is used as the fuels for the experiment ³ Foil - this is used to stop heat escaping for the fuels so
The differences between the Alkali metals and the Transition metals.
`The differences between the Alkali metals and the Transition metals In this essay I will explain the differences between the alkaline metals of Group 1 (la) in the periodic table and the Transition elements of groups 3 to 12 (lllb - llb) I will explain the reactivity, density, melting point, electronic metals and the uses. I will also compare the differences between the two groups. What are the Alkali metals? The alkali metals are a group of six elements that are in-group 1 of the periodic table. They have low melting points are soft compared to other metals and are so reactive that they are always combined with other elements. They are powerful reducing agents this meaning that they are always willing to lose an atom to have a complete outer shell that makes the element stable. What are the Transition elements? These elements are elements that share the same electronic orbital structure; this means that they have similar chemical properties. These elements are defined as 31 elements that have atomic numbers that range from 21-30, 39-48 and 71-80 in the periodic table .The transition metals sometimes take on negative oxidation states. There properties are similar to other metals: there similarities include malleability, ductility, high conductivity of heat and a high conductivity of electricity. The elements act as reducing elements or otherwise "Donors of electrons"
The Journey of a carbon atom.
THE JOURNEY OF A CARBON ATOM BY APRIL GRAY THE JOURNEY OF A CARBON ATOM Carbon atoms cycle through the earth and its biosphere. The carbon atom is part of a carbon dioxide molecule (co2) in the atmosphere. Carbon dioxide makes up less than 0.05% of the atmospheric gases. Some of the other major gases are nitrogen (N2), hydrogen (H2), oxygen (02) and water vapor (H20). Carbon atoms are absolute essential to life on earth. A carbon atom was drifting in the atmosphere when it descended down upon a colorful plant. As it glided over the top of the plants flower to the top of one of its leaves, it found it difficult to enter, however, after a drifting to the underside of the leaf (stomata) it was diffused and entered a palaside cell where it was then made into a glucose, starch this process is called photosynthesis. In this process, energy from the sun is being used to change it along with water drown up from the roots, into a simple sugar molecule (C6 H2 O6). Sugars are sometimes joined together to form large starch molecules. Both sugars and starches are known as carbohydrates. Oxygen gas is also formed and released into the atmosphere. One hundred and twenty five years ago, a dinosaur was walking through Wye Valley. The surrounding area was full of carbon atoms from the atmosphere, vegetation and exhaled air. The dinosaur was searching for food. As he walked around the
The purpose of this experiment is to see what factors affect the period of one complete oscillation of a simple pendulum.
SCIENCE COURSEWORK PENDULUM EXPERIMENT Aim The purpose of this experiment is to see what factors affect the period of one complete oscillation of a simple pendulum. In this investigation I am going to discover and investigate the factors, which affect the time for one complete oscillation of a simple pendulum. It is important to understand what a pendulum is. A pendulum has a weight or mass fixed and left hanging of the string. An oscillation is one cycle of the pendulums motion e.g. from position a to b and back to a. I will time how long it takes for one oscillation of the pendulum. I am going to do a simple preliminary experiment to investigate which of the factors I test have an effect on the time for one complete oscillation. The factors basic variable factors I can test are: ? Length (the distance between the point of suspension and the mass) ? Mass (the weight in g of the item suspended from the fixed point) ? Swing size (the length I release the pendulum) *The point of equilibrium is the point at which kinetic energy (KE) is the only force making the mass move and not gravitational potential energy (GPE). I will test the extremes of these factors as I can assume that if they have any effect on the period of oscillation it will become obvious. To make sure my results are accurate enough to allow for any anomalies I will repeat the experiment 2 times for each
Heat of Neutralisation - I am going to investigate the heat of neutralisation between acids and alkalis.
Heat of Neutralisation. I am going to investigate the heat of neutralisation between acids and alkalis. Prediction I predict that no matter what strong acid and alkali react together you will always get the same heat of neutralisation because the same reaction is always taking place. E.g. . HCl and NaOH 2. HNO3 and NaOH 3. NO3 and KOH . H++Cl¯+Na+ + OH¯ Na++Cl¯ + H2O H+ + OH¯ H2O 2. H+ + NO3¯+ Na++OH¯ Na+ + NO3¯+ H2O H+ + OH¯ H2O 3. H+ + NO3¯ + K+ + OH¯ K+ + NO3¯ + H2O H++ OH¯ H2O I am also going to react 2 weak acids (ethanoic acid and propanoic acid) with a strong alkali (sodium hydroxide.) I predict that the energy change i.e. the heat of neutralisation will not be same as before because with weak acids and alkalis some energy is required to fully ionise them. Heat of neutralisation is the heat change when an acid and an alkali react together to form 1 mole of water. Fair Test To ensure the investigation is made fair I will always use the same concentration of acid and alkali (1 mole.) The experiments will always be carried out at room temperature so the initial temperature is the same. I will also repeat the experiments to obtain good results, if the results vary in any way I will calculate the average. Apparatus Measuring Cylinders Pipettes Thermometers Polystyrene Cup Safety To ensure the experiments are carried
An investigation into the efficiency of an immersion heater 2
An investigation into the efficiency of an immersion heater Introduction: An emersion heater is primarily used to heat water. It does this by using electrical power and converting it into heat energy. The amount of energy supplied to the emersion heater will be worked out using the formula: Voltage Current Time. The heat gained by the water was calculated by using the formula: Mass of water Specific heat Temperature change. This will then be used to calculate the efficiency of the heater. Efficiency is how good the item being tested is at retaining energy: The ratio of the energy delivered by a machine to the energy supplied for its operation determines the items efficiency. I will use the following formula to calculate the immersion heater's efficiency. Energy supplied 100% Energy produced Method: Circuit diagram The apparatus and circuit were set up and arranged as shown in my diagrams above The measurements I will take are as follows: * initial temperature of water * amps after 2 minutes * volts after 2 minutes * temperature of water after 2 minutes To get a fair and average result I will change the type of wire I am using as well as the S.W.G of the wires but not the length of the wire so as to get a variety of results ands therefore see what wire is more efficient to use in the immersion heater. Results: Below are the tables of the results I got
electomagnet lab
PHYSICS LAB REPORT STRENGTH OF AN ELECTROMAGNET AIM: To investigate the factors that affects the strength of an electromagnet. THEORY: An electromagnet is a magnet that runs on electricity. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. The poles of an electromagnet can even be reversed by reversing the flow of electricity. An electromagnet works because an electric current produces a magnetic field. The magnetic field produced by electric current forms circles around the electric current, as shown in the diagram below: If a wire carrying an electric current is formed into a series of loops, the magnetic field can be concentrated within the loops. The magnetic field can be strengthened even more by wrapping the wire around a core. The atoms of certain materials, such as iron, nickel and cobalt, each behave like tiny magnets. Normally, the atoms in something like a lump of iron point in random directions and the individual magnetic fields tend to cancel each other out. However, the magnetic field produced by the wire wrapped around the core can force some of the atoms within the core to point in one direction. All of their little magnetic fields add together, creating a stronger magnetic field. As the current flowing around the core increases, the number of aligned atoms
Physics of water waves.
All waves possess the properties of reflection, refraction, diffraction and interference. These phenomena's were observed with the use of a ripple tank. A ripple tank consists of a large rectangular tray with a transparent bottom. Water is placed in this tan to a depth of approximately one centimeter. A light source is then placed above the tray of water. When the water is disturbed it can be seen on a white surface positioned under the tray. The first phenomenon observed was reflection. It was found that water waves also follow the law of reflection. As straight waves strike a hard straight surface they are reflected at an angle equal to the angle of incidence. After reflection the wave has the same speed, frequency and wavelength as it did prior to the collision. This is similar to the reflection of circular waves off a straight barrier. The reflected waves are also circular, however they have a centre point that is position behind the barrier. This point is known as the "image" of the source. Reflection of a parabolic or concave barrier can be closely compared to that of light waves off a concave mirror. If the incident wave was straight, the reflected waves are curved, and they converge at a fixed focal point. After passing through the focus, the radius of the curves increase. The opposite is so when circular waves strike a concave barrier. The reflected waves are
