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 effect of Hydrocholric acid on the Rate of Reaction
The Effect of Hydrochloric Acid on the Rate of Reaction Aim: My aim is to see if there is any change in the rate of reaction if the concentration of the acid increases. Variables: The independent variable in the experiment is the concentration of the hydrochloric acid; the concentrations are 0.1, 0.2, 0.3, 0.4 and 0.5M. The dependent variable will be the rate of reaction of the acid. The control variable is the amount of the concentration, the temperature of the acid and the time that the zinc is inside the acid. Hypothesis: My prediction is that as the concentration of the acid increases the zinc will react more but not necessarily quicker. In order for any reaction to happen, the particles must first collide. If the concentration is higher, the chances of collision are greater, thus resulting in a greater rate of reaction. Method: First I filled five different test tubes with the five different concentrations of the acid. I measured all of them to 20cm3. Then I collected five different pieces of zinc, and then weighed them on a scale. I recorded these results for later use. I made sure the temperature of the acids was the same using thermometers. I placed each piece of zinc in a different concentration and started the stop watch. After forty-five minutes I removed each piece of zinc and dried them with tissue paper. I then measured them with the same scales I had
Nanochemistry. Buckminsterfullerene is an allotrope of Carbon with a Formula of C60.
Nanochemistry: Buckminsterfullerene Buckminsterfullerene is an allotrope of Carbon with a Formula of C60. It was discovered in 1985 by scientist at the Universities of Sussex and Rice. It was discovered by Harold Kroto, James R. Heath, Sean O'Brian, Robin Curl and Richard Smalley. The group named it after Richard Buckminster-Fuller because the shape is that of a Geodesic Dome and he was a noted architect who favoured this shape and the scientists thought it suitable. The dome is one comprised of hexagons and Pentagons [see below] and many examples can be seen in botanical gardens (e.g Missouri and Montreal). Buckminsterfullerene was not discovered because people wanted to discover it: it was discovered purely by chance. Scientists were trying to understand about the absorption of interstellar dust and the theorised that they must have long chains of atoms. Further research with a molecular beam proved their theory right (to some extent), as there were not long chains, just one big ball - hence the nickname "Bucky balls". The other allotropes of carbon (diamond and graphite are giant molecular structures whilst Buckminsterfullerene is simple molecular. This means that the structures of diamond could go on forever whilst Buckminsterfullerene has a defined shape and the molecule has a maximum number of atoms [see above]. Buckminsterfullerene has a maximum of C70 whereas each
rates of reaction- hydrochloric acid
Rates of reaction Aim: The aim of the experiment is to investigate how the concentrations of hydrochloric acid effects the rate of reaction with magnesium, i.e. how quickly/ how much hydrogen is produced. Experiment Equations: - Magnesium + Hydrogen acid ? Magnesium Chloride + Hydrogen - Mg + 2HCl ? MgCl( + H( - Metal + Acid ? Metal Salt + Hydrogen Prediction: I predicted that the rate of reaction will increase when the concentration of hydrochloric acid increases. The reasons for this is because the more particles there are moving around in one place the more chance there is of a collision between the particles with sufficient energy to create a reaction. In the higher concentrations of hydrochloric acid there is more acid particles to collide with the magnesium therefore a higher rate of reaction. Safety: During the practical various measures must be taken to ensure the experiment is carried out safely. These measures are; - Always wear safety goggles (at all times) to ensure no chemicals make contact with eyes. - Avoid contact of acid on skin as it is corrosive. If acid does touch skin wash it off (immediately). - Don't run in labs, no food or drink. - No concentration of hydrochloric acid greater than 2 molar, anything larger is dangerous. - Clean up any spillages immediately. Equipment list: - Boiling tube = this is where the chemical reaction takes
In this CDA I will write about how plastic bags are made, why plastic bags are so controversial, the benefits and drawbacks of using them, and I will include an experiment that I carried out at school to determine the strongest plastic bag (out of various
Plastic Bags CDA Today, the world's use of plastic has increased drastically from about 5 million tonnes in the 1950s to almost 100 million tonnes in 2001. This means that we now produce 20 times more plastic! 35% of all plastics used in the UK are used for packaging, a proportion of which, being plastic bags. Around the whole world, 500 billion to 1 trillion plastic bags are used every year, and shockingly 1 million plastic bags are being used every minute. But when a single plastic bag takes 1000 years to degrade, the environment is in danger. Thankfully, a lot of plastic bags today are suitable for recycling, but according to the BBC only 1 in 200 bags are recycled. So when a small percentage of plastic bags are recycled, where do they really go? Are plastic bags good or bad? Do the positives of using plastic bags outweigh the negatives? At school we were looking at effects on the environment due to human activity and possible natural causes. In this CDA I will write about how plastic bags are made, why plastic bags are so controversial, the benefits and drawbacks of using them, and I will include an experiment that I carried out at school to determine the strongest plastic bag (out of various different brands). Also, I will include my opinion and the reason for my conclusion. What are plastic bags? A plastic bag (also known as a carrier bag) 'is a type of flexible
Area & Volume Exploration – Component proportional changes
Area & Volume Exploration - Component proportional changes Question 1: How do the Volume, Surface Area and Mass of your component vary when two key dimensions are changed but the length remains the same? Changing one key Dimension by 5%, 10% & 20% Increasing the length: 20m 5% increase => 20 ? 5% = 1 100 => 20m + 1m (increase) = 21m So... New cuboid dimensions = Length = 21m Width = 10m Height = 5m Volume = 10m ? 21m ? 5m = 1050m3 S. Area = (2?10?5)+(2?21?5)+(2?10?21) = 100 + 210 + 420 = 730m3 Mass = 7800kg/m3 ? 1050m3 = 8'190'000kg This clearly shows that when the length is increased by 5% the Volume and Mass are also increased by 5%. This indicates that the Volume and Mass are directly proportional to the length. The Surface Area would not appear to be directly proportional to the length as it does not increase by 5%. Further exploration is needed to confirm that this proportional increase is not a one off event. I predict that the same will happen and the percentage increase will be the same for Length, Volume and Mass. 10% increase => 20 ? 10% = 2 100 => 20m + 2m (increase) = 22m So... New cuboids dimensions = Length = 22m Width = 10m Height = 5m Volume = 10m ? 22m ? 5m = 1100m3 S. Area = (2?10?5)+(2?22?5)+(2?10?22) = 100 + 220 + 440 = 760m3 Mass = 7800kg/m3 ? 1100m3 = 8'580'000kg Volume = 10m ? 27m ? 5m = 1350m3
History of Chemistry and Atomic Structure.
History of Chemistry and Atomic Structure Greeks - First to consider the nature of matter (400 BC) ) Two camps: a) matter is continuous - keep on dividing matter indefinitely; you just get smaller pieces Aristotle believed that matter was continuous b) matter is finite; it is composed of small indivisible particles Democritus - everything made up of atoms (atoms - Greek for "indivisible") 2) 4 different types of "elements" or "atoms" : Fire, Earth, Water, Air How were these 4 types of "atoms" different - they were especially interested in shape since Greeks were really into geometry: Fire - jagged shaped, since fire hurt Water - spherical, smooth since water flowed easily Earth - cubical - earth was solid and stable 3) The Greeks were not doing science as we know today but an intellectual exercise (philosophy) since no evidence existed one way or the other and they had no experiments to test their ideas (science) 4) Aristotle held more prestige and his ideas about matter held on for almost 2000 years. Alchemists ( 0 - 1500AD) Based upon the idea that there were only 4 different types of matter, the variety all around them lead scientists to believe that each different substance (say lead and gold) must be made up of different proportions of the 4 "elements". If one could separate the 2 elements and recombine them in different proportions, one could
To demonstrate the principle of osmosis, the diffusion of water through a semi permeable membrane.
Osmosis in Plant Cells Aim- to demonstrate the principle of osmosis, the diffusion of water through a semi permeable membrane. Apparatus: * 3 carrot slices * 3 raisins * 6 small labels * 6 thin plastic containers * 2x25 ml of distilled water (0 M ) * 2x25 ml of salty water ( 0.5 M ) * 2x25 ml of salt water ( 1 M ) * measuring cylinder * Balance Diagram: Method: ) Distilled, salty, and salt water was measured using a measuring cylinder, and placed into 6 plastic containers. 2) The containers were labeled, and distributed in three pairs. 3) Each individual carrot/raisin was weighed. 4) The apparatus was then set as shown on the diagram. 5) The carrots and raisins were left over 40/45 minutes. 6) Each individual carrot/raisin was weighted once again. 7) Results were recorded and observations taken down. Results: Carrots Salt Concentration (M) Mass of carrot before (g) Mass of carrot after (g) 0 M 3.34 g 2.24 g 0.5 M 3,47g 2.55 g M 3,67 g 3.67 g Observations after % change in Mass Difference in Mass (g) smoother appearance, lighter 32.9 % .1 g quite crumpled 26.5% 0.92 g quite crumpled, nearly equal 0% 0 g Raisins Salt Concentration (M) Mass of raisin before (g) Mass of raisin after (g) 0 M 0.24 g 0.37 g 0.5 M 0.37 g 0.40 g M 0.19 g 0.20 g Observations after % change in Mass Difference in Mass (g) Sobby,
Structures of the Different Allotropes of Carbon.
Sagar Manilal Chemistry 11b 05-Jan-2004 Structures of the Different Allotropes of Carbon Carbon is a very crucial element as it is there everywhere we see, it even is in our own bodies. Carbon is present in our everyday lives such as in the food and even in air which we use to survive on a regular basis. Diamonds are another form (allotrope) of carbon in is currently the strongest known substance to man. This element is in the 2nd period and 4th group of the periodic table and has a total of 6 electrons with valency of 4 electrons. These outer shell electrons allow us humans to understand its nature and so we know that is shows covalent properties and undergoes covalent bonding. This sort of bonding occurs when the electrons in the outer shell of the element bond with another element by a mean of sharing electrons where electrons are neither lost nor gained in this process. As they have four electrons in the outer shell, it has four covalent bonds as they will have a total of eight electrons with is the total number of electron this particular shell can hold. The covalent bonding in this atom is very special as it forms many diverse crystalline or molecular structures. These different molecular structures of carbon are known as allotropes. An allotrope is the existence of elements in two or more different forms. Carbon has three major allotropes, and they are; diamond,
GCSE Chemistry - Sodium Thiosulphate
We must produce a piece of coursework investigating the rates of reaction, and the effect different changes have on them. The rate of reaction is the rate of loss of a reactant or the rate of formation of a product during a chemical reaction. It is measured by dividing 1 by the time taken for the reaction to take place. There is five factors which affect the rate of a reaction, according to the collision theory of reacting particles: temperature, concentration (of solution), pressure (in gases), surface are (of solid reactants), and catalysts. I have chosen to investigate the effect temperature and concentration have on a reaction. This is because they are the most practical to investigate - it would take longer to prepare a solid in powdered and unpowdered form, and it is difficult to get accurate readings due to the inevitabilities of human errors, and as gas is mostly colourless it is difficult to gauge a reaction changing the pressure, and if a substance is added to give the gas colour, it may influence the outcome of the experiment. Similarly the use of a catalyst complicates things, and if used incorrectly could alter the outcome of the experiment. Aim: - To see the effects of a change in temperature and concentration on the rate of a reaction. The reaction that will be used is: Sodium Thiosulphate + Hydrochloric Acid Na2S2O3 (aq) + 2HCl (aq) Sodium Chloride + Water
