Galileo and the moon
'Galileo had discovered many wonderful things which are very useful, even in the present life. At 20 while in a cathedral Galileo investigated the time it takes a lamp to swing using his very own heartbeat as a timer, and he realised that the each swing took the exact same time. In addition he invented the thermometer and a military compass to aim cannonballs which still are useful and ingenious. He did not invent the telescope but produced his own and used it to investigate the Moon and realised that it was not as smooth as first though, but full of craters and rough surface. At first he was rejected, and a mathematician stated that the moon was covered in 'invisible, transparent, smooth crystal.' Also Galileo said that the Moon like the Earth consisted of valleys and Mountains and that the dark spots were created by the Sun producing shadows. Then using his 30x power telescope Galileo focused on Jupiter and found three stars all in a straight line to each other. However Galileo was very secretive he wrote his discoveries as anagrams, so that it did not escape to others. Finally he concluded that Jupiter had three satellites which orbited Jupiter. This made Galileo suspicious if the earth was the centre of our solar system as the three 'stars' orbited Jupiter. Although Galileo thought that the sun was the centre of our solar system, he failed to accept this himself as he was
pH Lab Report - testing household liquids
Alyssa Bellave Living Environment 0/26/11 Mrs. Padilla pH Lab Introduction: Substances, even household substances, can be acidic, basic, or neutral. Acids and bases are called aqueous solutions, or mixtures of certain substances dissolved in water. The amount of acidity or basicity can be measured by using the pH scale. The scale runs from 1-14. The scale has to do with the amount of hydrogen ions [resent in a substance. Hypothesis: Our hypothesis for this experiment consists of twelve different substances. The tomato juice will be acidic; the distilled water will be neutral; the Windex will be basic; the vinegar will be basic; the soda will be basic; the milk will be neutral; the buttermilk will be neutral; the baking soda solutions will be acidic; the "green" cleaner will be basic; the household cleaner will be acidic; the Lemon Juice will be acidic. Materials: For this lab we need pH paper, a spot plate, water (distilled, if available), and substances with varying pH. Safety: In this lab we must were goggles and aprons to avoid skin contact with all chemicals that are going to be used in this experiment. If it does happen, we must report any skin contact or chemical spills to our instructor immediately. Procedure: First we get a spot plate and put three to four drops of each liquid substance in each of the wells. The liquid must correspond
Investigate the relationship between GPE (Gravitational Potential Energy) and KE (Kinetic Energy) for a trolley or ball rolling down the slope.
GCSE PHYSICS Coursework Data Analysis/Handling-Investigation To investigate the relationship between GPE (Gravitational Potential Energy) and KE (Kinetic Energy) for a trolley or ball rolling down the slope. Candidate Name: Leah McDonald Centre Name: Dunraven School Candidate Number: 7125 Centre Number: 10920 Strategy We were asked to complete an investigation into the energy associated with a trolley rolling down a slope. At first I wasn't sure exactly what question I wanted to investigate so I carried out the following preliminary investigations: Preliminary Experiment 1: Time= 1.28 seconds Average Velocity =50.0/1.28 Using a stop timer still leaves Human error,-human reaction Time. Preliminary Experiment 2: Time=678.49 ms(milliseconds) second = 0.001 ms Time=0.67849 seconds Average Velocity =0.50 0.67849 0.73 m/s NOTE: The data logger was set to 'timing and then 'timing from A to B' Preliminary Experiment 3: Time= 7.36 milliseconds Instantaneous Velocity= 0.01 0.00736 =1.20 m/s NOTE: The data logger was set as 'timing' and then 'timing at A' mode After completing my preliminary experiments, I thought that the most promising ling of investigation was Preliminary Experiment 2, because the Data Logger gives an advantage, which removes the disadvantage of Human Reaction time. makes it more likely for my results to be more accurate. So the
Identifying an Ionic Compound. Objectives: To learn and test for metal ions and non-metal ions and then apply them to discover the identity of an unknown ionically bonded substance
Identifying an Ionic Compound- Introduction Ionic compounds are defined as being compounds where two or more ions (an atom or group of atoms with an overall electrical charge) are held next to each other by electrical attraction. One of the ions has a positive charge - called a "cation", and the other has a negative charge - called "anion". Cations are usually metal atoms and anions are either nonmetal or polyatomic ions (ions with more than one atom). Usually, when we have ionic compounds, they form large crystals that you can see with the naked eye. Table salt is one of this- if you look at a crystal of salt, you can see that it has in irregular cube shape. This is because salt likes to stack in little cube-shaped blocks. When forming salt, Na readily loses an electron and Cl readily gains an electrons so both can become stable. Heat is added in the reaction so Na burns brightly in CL gas and a white solid forms on the sides of the container. This solid is salt, or sodium chloride. When the chlorine atom gained an electron, the atoms arrange themselves in a lattice. The force of attraction between a cation and anion is a very strong bond called an "ionic bond". This is an electrostatic attraction. An ionic bond happens between a metal and a nonmetal. Properties of salts: 0. All ionic compounds form crystals. 0. Ionic compounds tend to have high melting and boiling
Artificial Cardiac Pacemakers
Research questions : Why is the constant beating of the heart important? What causes the heart to beat abnormally? What are the implications of having an abnormal heart beat? What is an artificial pacemaker and how does it regulate an abnormal heart beat? How are artificial pacemakers implanted? What are the advantages and disadvantages of using an artificial pacemaker? What are some alternatives used instead of artificial pacemakers? The importance of the heart The heart is an essential organ possessed by every living human. It is vital as it pumps blood rich in oxygen (received from the lungs) to every living cell within the body and pumps deoxygenated blood to the lungs (from the body)1. In the opposite diagram of a human heart, the blue sections represent the transport of deoxygenated blood and the red sections represent the transport of oxygenated blood. The heart is necessary in sustaining the lives of every single human being. This is because without oxygen, cells cannot carry out the process of cellular respiration (the release of energy from glucose). This means that the body cells will have insufficient energy to carry out regular functions needed for sustaining life. Every single cell in the human body is affected by the beating of the heart, as enough oxygen has to be supplied for them to function properly. Without the constant beating of the heart,
I measured the effect of concentration on the rate of reaction. The reactants were Sodium thiosulphate and Hydrochloric acid.
Data Analysis - Chemistry Coursework The effect of concentration on the rate of reaction ANALYSIS: For my data analysis, I measured the effect of concentration on the rate of reaction. The reactants were Sodium thiosulphate and Hydrochloric acid. This reaction made the products sodium chloride, sulphur dioxide, sulphur and water. When an acid is added to sodium thiosulphate, a yellow, cloudy precipitate is formed. And, as the sodium thiosulphate becomes more and more diluted, the solution takes longer and longer to form. However, in order for the reaction to take place, the reactants must first collide with each other. The collision theory should take place with the minimum amount of energy; this is called the activation energy. Head on collisions contain more energy, if collisions have enough energy then the collision that took place is successful and therefore a reaction occurs, however this isn't the case with all collisions. The collisions happen regardless of whether both the particles are in the solution, or whether one is in the solution and the other is a solid. The chances of collision are higher when the concentration is higher. For many reactions that involve liquids or gases, the increase of concentration on the reactants will increase the rate at which the reaction takes place. The point at which the reaction starts is called the energy barrier. When this
Rates of Reaction Practial
Rates of Reaction Practical Aim: The aim of this investigation is to investigate how the rate of reaction of Calcium Carbonate (CaCO3) with Hydrochloric acid (HCl) could be affected by surface area. Equation: HCl(aq) + CaCO3(s) CaCl2(aq) + CO2(g) + H2O(l) Hypothesis: I predict that the more the surface area the faster the rate of reaction because it increases the chances of collision. This is because more calcium carbonate is exposed to the acid molecules so they are more likely to collide. When measured in the same mass the smaller chips have a larger surface area altogether. Here is a diagram to show this: (if cut into 8 equal pieces) ==> Apparatus: - Two beakers (400ml) - Large Calcium Carbonate Chips (5g) - Small Calcium Carbonate Chips (5g) - Calcium Carbonate Powder (5g) - Hydrochloric Acid 1M (100ml) - Spatula - Accurate Scale - Stopwatch Method: . Collect all of the equipment and measure 5g of each size of surface area of Calcium Carbonate with a spatula. 2. Collect 100 ml of Hydrochloric Acid into one of the 400ml beakers. 3. Place the other beaker on the scale and then set the scale measure to zero. Pour the 100ml of HCl into the beaker on the scale. 4. Hold a stopwatch in one hand, and place the
My experiment will be conducted to find out at what concentration does sodium thiosulphate with hydrochloric acid have the most reaction and how the concentration generally affects the rate of reaction.
How does concentration affect rate of reaction? I am going to conduct an experiment on rate of reaction and how the concentration of sodium thiosulphate affects the rate of reaction. Several things such as temperature, ph and concentration can affect the rate of reaction. My experiment will be conducted to find out at what concentration does sodium thiosulphate with hydrochloric acid have the most reaction and how the concentration generally affects the rate of reaction. Particle size has a big impact on the speed of a reaction, if the particles are big then the reaction would be slow but if the particles are small the reaction will be fast. A catalyst often changes a reaction rate and they increase the speed of reaction always. The rate of reaction for this experiment will be measured by timing how long it takes for the sulphur from the sodium thiosulphate to cover an 'x' under a beaker. To test the rate of reaction and what affects it, we could have tested the effect of ph on rate of reaction, but that was not complicated enough. We used: * Sodium thiosulphate * Water * Hydrochloric acid Dilute sodium thiosulphate with water according to these measurements: Concentration HCL THIO H2O 00% 20ml 60ml 0ml 75% 20ml 45ml 5ml 50% 20ml 30ml 30ml 40% 20ml 24ml 36ml 25% 20ml 45ml 5ml How we carried out the investigation ) Prepare equipment 2)
Aim To investigate the effect of different masses suspended from a spring on the time period of the spring.
THE EFFECT OF A SUSPENDED MASS ON THE TIME PERIOD OF THE SPRING. Aim To investigate the effect of different masses suspended from a spring on the time period of the spring. Hypothesis I feel that if I increase the mass, the period will increase too because the mass is proportionate to the time period. Variables > Independent - Mass suspended from spring. > Dependent- The time period of the string. > Constant- The apparatus, Number of oscillations, spring constant (elasticity). Apparatus > 1 spring > 100 gram masses. (6 of them) Materials > 1 clamp stand > Stopwatch > Plasticine Method . Place a clamp stand on the table 2. Attach the spring to the clamp stand. 3. Add heavy books on the clamp stand to the base so that it is stable and doesn't affect our readings. 4. Add Plasticine to the top of the spring so that the spring itself doesn't vibrate a lot. Hence there would be no discrepancies in the readings. 5. Add 100 grams mass to the spring. 6. Displace the 100 gram mass. 7. Release the 100 gram mass and at the same time start the stopwatch. 8. Record the time taken for 10 oscillations. 9. Repeat steps 6 to 8 2 more times to get three total trials. 0. Now add more mass to the spring and repeat steps 6 to 8 with 200 g, 300g, 400g, and 500g. Diagram Raw Data Table Mass (grams) Time taken for 10 Oscillations (seconds)( +/- 0.01 secs) Trial
Investigating Osmosis: The Molarity Of A Potato Cell.
Investigating Osmosis: The Molarity Of A Potato Cell Introduction Knowing that osmosis (diffusion of water) will occur across a semi-permeable membrane whenever there is a difference between the water concentrations on the two sides of the membrane, and knowing that when this happens to cells, they will either become turgid if water flows into them, or plasmolysed if water flows out of them, therefore changing their volume. I want to test the hypothesis that: If the concentration of a solution into which a cylinder of potato is placed is greater than a certain level the cylinder will decrease in mass, and if the concentration is less than that level it will increase in mass. Prediction I believe from my past knowledge of a similar experiment involving raw eggs that the potato cylinders placed in the distilled water will be hypertonic, therefore the water will diffuse by osmosis into the potato from an area of high concentration down the concentration gradient. This will result in a gain of mass for the potato. However in the 1.0M solution I think that the opposite will occur as there will be a higher concentration of water within the potato than the solution, this will make the potato hypotonic and it will lose its water content as the water diffuses out. A difference between the egg experiment and the potato experiment is that the potato cells will not reach a
