Investigating the factors affecting the strength of an electromagnet.
* Investigating the factors affecting the strength of an electromagnet * Background Knowledge: The theory of magnetism is the only way to explain the process of magnetising an object. In an unmagnetised piece of iron the domains are pointing in numerous directions, which results in them cancelling each other out. However, a magnetised piece of iron would have all the magnetic domains pointing in all the same direction. This is due to the north poles being at one end and the south poles at the other end. The domains are actually extremely small atomic magnets that line up with each other to form groups, called domains. All iron and steel are made up out of millions of these domains. The magnetic field is the area around a magnet where it has a magnetic effect. The shape of a magnetic field can be determined by placing a thin layer of iron filings over paper with a bar magnet underneath. When the paper is gently tapped the iron filings act like tiny compasses and point themselves along the lines of flux. The magnetic field of an electromagnet is the same as a bar magnet and it looks like this: Electricity has a magnetic effect; a wire carrying a current has a magnetic field round it. The magnetic field around a wire is in the shape of circles. The magnetic effect can be strengthened by: -Using a larger current -Using more turns of wire on the core -Using a soft iron
Scientific Practical Techniques
BETC National Diploma in Applied science/ Medical Science Scientific Practical Techniques Assignment number one Task 2 ) For this task I have done four different investigations, which is Hook's law, pH four unknown liquids, examine voltage, current change and growing yeast culture. Hook's law Hook's law given the relationship between the force applied to an unscratched spring and the amount the spring is stretched when the fore is applied. The purposes of this experiment is to see when we apply a force what will happen to the spring, therefore when we apply a force to a spring it will stretches, and if we apply double force it will stretches twice as much. I performed this experiment to determine how the extension of a spring varies with the stretching force. A spring is hung vertically from a fixed point and a force is applied in stages by hanging weights from the spring. The apparatus is set up as shown above. For the purpose of the experiment I used different gram 50 to 400 gram, and the extension of the spring I measured it metres. To start the experiment first I measured the unloaded length of the spring without touching, and then add the 50g loads, doing the same one at a time for all loads and measure the length of the stretched spring, and I recorded the results in the table. Load/ g Extension /mm 0g 0mm 50g 95mm 00g 30mm 50g 60mm 200g 90mm
See how different concentrations of yeast affects how much oxygen is given off in 1 minute, when 10cm3 of yeast (which contains catalyse) is mixed with 10cm3 of hydrogen peroxide.
Catalase is an enzyme found in all living cells. It makes Hydrogen Peroxide decompose into water and oxygen. You can represent this in the equation: 2H2O2 =2H2O + O2 Enzymes: Enzymes are able to increase the rate of reaction without actually being consumed in the process. In all, enzymes are very efficient. Small quantities at low temperatures are able to produce results, which would require high temperatures and a violent reaction from any normal chemical means. Although increases in temperature may speed up the reaction, enzymes are unstable when heated. There are three important definitions that are used when talking about enzymes: - The substance that enzymes act on is the substrate. The substance formed by the reaction is the product The site on which the enzyme takes place is called the active site. Enzyme function can be explained by the Lock and Key Hypothesis: the active site of an enzyme (the lock) has a specific shape in which only the precise amount of substrate (the key) will fit - forming an enzyme-substrate complex. Therefore producing a product. All enzymes have the following 4 properties: · All enzymes are proteins · Enzymes are catalysts · Enzymes are denatured by high temperatures · Enzymes work best at a certain pH (normally 7) The Effect of Enzyme concentration: As long as the concentration of the substrate is much
Pros and Cons of Genetic Engineering
Pros and Cons of Genetic Engineering Introduction The first step to understanding genetic engineering and embracing its possibilities for society is to obtain a rough knowledge base of its history and method. The basis for altering the evolutionary process is dependant on the understanding of how individuals pass on characteristics to their offspring. Genetics achieved its first foothold on the secrets of nature's evolutionary process when an Austrian monk named Gregor Mendel developed the first "laws of heredity." Using these laws, scientists studied the characteristics of organisms for most of the next one hundred years following Mendel's discovery. These early studies concluded that each organism has two sets of character determinants, or genes. For instance, in regards to eye colour, a child could receive one set of genes from his or her father that were encoded one blue, and the other brown. The same child could also receive two brown genes from his or her mother. The conclusion for this inheritance would be the child has a three in four chance of having brown eyes, and a one in four chance of having blue. Genes are transmitted through chromosomes which reside in the nucleus of every living organism's cells. Each chromosome is made up of fine strands of deoxyribonucleic acid, or DNA. The information carried on the DNA determines the cells function within the organism.
Properties of Waves.
Properties of Waves There are many different waves including water, sound, light and radio waves. All waves have the same range of properties, they can all be reflected, refracted, totally internally reflected, diffracted or interfere with each other. Waves are repeated oscillations (vibrations) which transfer energy from one place to another. Sound energy in the atmosphere is transferred by the oscillation of air molecules. Movement energy in water waves is transferred by the oscillation of water molecules. Amplitude is the measure of the energy carried by it. Frequency (f) is the number of complete wave cycles per second and is measured in Hertz (Hz). Wavelength (?) is the distance between two successive peaks or troughs and is measured in metres, m. Reflection Light waves travel in straight lines but reflecting them using mirrors can alter their direction. Reflection is the bouncing off of any type of wave from a surface. Reflection can be used to guide a laser past obstacles to a receiver. Shiny surfaces such as mirrors are smooth so reflect all light strongly as all the waves pass in one direction only. Rough surfaces look dull as they reflect light in many different directions causing it to scatter. This is called diffuse reflection. If light waves are reflected, the colour of the surface affects the colour of the reflected ray. Concave surfaces are used
The Renal System.
The Renal System: The renal system consists of the bladder, kidneys (the kidneys are approximately eleven-cm long, six cm wide and four cm thick), urethra and the ureters. The kidneys are placed under the bottom of the rib cage and close to the spine. There are two functions of the renal system; these are to get rid of waste materials and to control the level of water in the body. Waste materials are removed from the blood and pass out through the body during the process of excreting urine. The levels of water in the body are controlled to ensure that the concentrations of different liquids within the body are kept within safety limits. This process is called osmoregulation. The kidney's function within the body is to clean the blood and get rid of anything the body doesn't want or need or that is harmful to its self. There is a large amount of space in the kidneys. People can not only survive with one kidney but also lead very healthy, active lives if they choose to do so. If a person is unfortunate to suffer from complete kidney failure, the blood allows waste materials to build up within the body as a result the levels of toxicity in the body rises. The body will eventually become poisoned internally if the kidneys can't clean the blood. Urea is produced in the liver; it is white in colour and is a crystalline substance. As the body doesn't store protein instead it
Thermal Decomposition of Copper Carbonate
Thermal Decomposition of Copper Carbonate ( CuCO3) Introduction: Copper Carbonate (CuCO3) decomposes by heat to form either one of two oxides, namely Copper (I) Oxide (Cu2O) and Copper (II) Oxide (CuO). This reaction can be written as two different equations: a. 2CuCO3 (s) --> Cu2O (s) + 2 CO2 (g) + 1/2 O2 (g) b. CuCO3 (s)--> CuO (s) + CO2 (g) Aim: In this experiment we will be required to identify the correct balanced stoichiometric chemical equation for the decomposition of the copper carbonate from the volume of carbon dioxide produced. Background Information: When metals are heated they react with oxygen in the air. As the metal is heated it reacts with the oxygen to form an oxide. Column II carbonates are decomposed by heat to form corresponding oxides and carbon dioxide. The temperature of decomposition depends on the reactivity (in relation to stability) of the metal. In this way, the carbonates of sodium and potassium are stable at the highest temperatures of a Bunsen burner flame whereas the carbonates of silver and copper are easily decomposed. Basic Idea: a. Copper carbonate will be heated b. Decomposition will occur c. A gas will be released and it will be collected. d. The volume of the gas that will be collected will give us an indication as to which equation is correct. Calculations - Hypothesis: (Essential Information) 'At room
Thermometric Titration
CHEMISTRY COURSEWORK (II) THERMOMETRIC TITRATION by Andrew McLorn Planning Normally we use an indicator when doing titration experiments, in this experiment we will not be using an indicator. Instead we will be monitoring the temperature of the solution. When an alkali is mixed with an acid heat is given out, this is called an exothermic reaction. The temperature goes up until the acid is neutralised and then no more heat is given out because the reaction is over. Adding more alkali causes the temperature to decrease. Apparatus .retort stand and clamp .burette .pipette .small beaker containing HCl .small beaker containing NaOH .funnel .polystyrene cup thermometer Method )collect apparatus 2)pipette 25cm3 of acid 3)put the acid in to the polystyrene cup 4)fill burette with NaOH 5)put thermometer in polystyrene cup and note temperature 6)add 5cm3 of NaOH, stir the solution and note temperature 7)keep adding NaOH at 5cm3 intervals, stir and note temperature between each addition of NaOH Displaying the Results Results should be displayed in a graph and a table like the one shown below: Safety The following safety precautions should be observed when carrying out this experiment: .assemble apparatusin the centre of an uncluttered bench .take care as acid is being used .wear goggles Conclusion As expected, the temperature of the solution increased
THERMOMETRIC TITRATION
CHEMISTRY COURSEWORK THERMOMETRIC TITRATION Aim The purpose of this experiment is to determine the concentrations of two acids, hydrochloric acid, HCl, and ethanoic acid, CH3CO2H, by thermometric titration; and having done that, to calculate the enthalpy change of neutralisation. Introduction You titrate both hydrochloric acid and ethanoic acid in turn with a standardized solution of sodium hydroxide and record the temperatures of the mixtures during the course of the titration. In each case a plot of temperature against time will enable you to determine the maximum temperature rise, from which you calculate both the concentration of the acid and the enthalpy change of neutralisation. Requirements * Safety spectacles * Pipette, 50.0 cm3 * Pipette filler * Expand polystyrene cup * Sodium hydroxide solution , 1 m NaOH (standardized) * Thermometer, 0-50 C0 (in 0.1 C0) * Burette , 50.0 C0 cm3 * Filter funnel , small * Hydrochloric acid , M HCl * Ethanoic acid, M CH3CO2H Safety/risk assessment: During experiment in laboratory extreme care should be taken to avoid any hazards. You should wear all the safety equipment at all times during the experiment. Eye Protection: Make sure that your eyes are fully protected. Goggles should be worn at all times during the experiment in the laboratory. Laboratory Coats: Lab coats should be worn during experiment to avoid
"To Clone or Not to Clone- That is the Question".
One World Essay "To Clone or Not to Clone- That is the Question" For years and years, the cloning of living beings has just been an aspect of science fiction. Although several movies have been created based on human cloning as such, their scientific accuracy has made the general public dismiss them as something not capable of in the near future. When the first ever living clone of a six-year-old sheep was created (to the right), the world was in an uproar. Dolly, the sheep clone named after singer Dolly Parton, had been cloned from the udder cell of an adult ewe by a group of scientists in Scotland. People realized that this breakthrough could be a door to unimaginable technology, not necessarily positive. The notion that this discovery could change the world and lives was beginning to threaten the minds of activists and others. Many of the fears that come with these theories are within cultural and religious beliefs, or from being exposed to too many movies. Films of human cloning depict terrible things that happen to those that tamper with nature. A very famous example of this is Mary Shelley's tale of Frankenstein. Even through historic cases, such as where Nazi doctor Joseph Mengele flees to Brazil after the crash of the Nazi rule and World War II and attempts to use Hitler's tissue to create several more Hitlers, people have wondered whether it was truly possible. When
