Essays on Chemistry

Procedure for Negatively Charged Ions (CHIC-) Use the same procedure as outlined above, then as a last step add one electron per negative charge to fill octets. Carbonate ion has a 2- charge, so we have two electrons available to fill octets. Using the procedure above, we arrive a this structure: The two singly-bonded oxygen atoms each have an open octet, so we add one electron to each so as to fill these octets. The added electrons are shown with…...

Proof of the Alcohol Solution: (Percent of Alcohol Based on Volume) (2) = Proof of the Alcohol Solution = (17. 6 96) (2) = 35. 2 Conclusion The experiment was very successful. The experiment went exactly as planned in all three parts. In part I and II of the lab, density of ethanol and water was calculated. The density of water was . 907 g/ml and the density of ethanol was . 724 g/ml. Since the density of ethanol is…...

PGTP Karachi Institute of Power Engineering (KINPOE) -CHASNUPP Centre of Nuclear Training (CHASCENT) PAKISTAN ATOMIC ENERGY COMMISSION P. O. BOX NO. 3183, Paradise Point, Hawks Bay Road, Karachi Phone: 021-99202222 Ext: 2701 Fax: 021-99202240 E-mail: [email protected] edu. pk Website: www. kinpoe. edu. pk APPLICATION FORM – 2010 Post Graduate Training Program (Nuclear Technology) at CHASCENT (Mianwali) and KINPOE (Karachi) (Read instruction before filling the form) Roll NO. __________________ (to be filled by JAC) 1. 2. 3. NAME: (AS APPEARED IN…...

Over the years, many different advances in technology have made the use of DNA in forensic science possible. In the past twenty years specifically, there have been many extraordinary discoveries In the fields of science that have led to the advancement of procedures in forensics. Before DNA testing, the most accurate way of identifying people was to match the blood types of suspects with blood found at the scene of the crime. Considering the lack of variability of this procedure,…...

Osmosis is the dispersion of water. Our cells are capable of absorbing nutrients because, the cell membrane is selectively permeable (some molecules can effuse freely through the membrane while others cannot). In this experiment we used dialysis bag as a model of the cell membrane. Our hypothesis was that the glucose will diffuse out of the membrane into the beaker filled with iodine solution. To demonstrate dialysis tubing we used water, starch and iodine. When starch and iodine react together…...

Osmosis/Plasmolysis Lab Name: Problem: How do solutions of various salt concentrations influence osmosis in relation to an onion cell? Materials: (per student group): red onion epidermis forceps, dropper distilled water NaCl solution paper towels microscope slidecover slip Procedure 1. Make a wet mount of the red onion epidermis. 2. Examine under low power. When you have a clear view of several cells, switch to high power. Make a labeled drawing (cell wall, membrane, cytosol) of your cells. This will give…...

Our objective for the Sherlock Holmes Experiment was to illustrate that some chemicals can be identified or differentiated by simple chemical tests, such as solubility, pH, or color tests. In our group we had to test come common powders such as Alkali-Seltzer, baking soda, flour, Vitamin C (ascorbic acid), and salt. Other chemicals that were used to do this experiment were vinegar, and Iodine 2 Solution. The equipment used to do this experiment was red litmus paper, and 5 test…...

One of the most memorable quotes I remember hearing was “The first time you see your child you will understand the true meaning of love. ” I never understood those words mainly because I was a twenty-one year old college student focused on school, my career, and most importantly my social life. Then on May of 2008 my favorite quote was about to become a quick realization of what I could expect and I would have a new understanding because…...

One Planarian Labels Scalpel Pipette Petri Dish Ruler (mm) Spring Water Safety Concerns: Sharp Objects Proper Attire Procedure: 1) Wear proper attire before starting the experiment. 2) Pick up the planar Ian with a pipette and put in the Petri dish with spring water in the dishes. 3) Label the Petri dish with the names and date. 4) Observe the planar Ian and record the initial length of the planarian in millimeter by using a ruler. 5) Cut the planarian…...

One reason that studying memory and organisation may be interesting is because the area was neglected, up until the 1990’s, when psychologists became interested in how an ‘enormously important but complex facility operates in people’ after being stimulated by the attempts to provide information about computer systems and how information is organised.( R.Gross, Hodder and Sloughton) One theory in relation to memory suggests that organisation may occur at two separate stages of memory. Meyer said ‘to remember is to have…...

Nuclear energy is a powerful source of energy compared to other conventional fuels. All crude oil based fuels derive their energy from oxidation, which is a change in the energy levels of electrons outside the nucleus. However, nuclear energy derives power from changes in the nuclear energy levels of the atomic nucleus! Tremendous energy lies locked up inside a radioactive nucleus and nuclear fission is a way of tapping this energy. Nuclear power plants derive energy from controlled nuclear fission reactions. This…...

Name: Compare And Contrast Judaism Christianity And Islam Compare and Contrast Judaism, Christianity and Islam Judaism, Christianity and Islam are the three major religions in the world. Together, the three groups account for almost four billion followers. In the past, countries, and regions within countries have identified themselves with one of the religions. In many cases, this has resulted to tension, conflicts and wars. Some countries have largely identified themselves as followers of one religion. In such cases, people who…...

Which in turn would give lower liters per mole ratio and State that there is less H2O gas then there actually is. Molar Volume Calculation for distorted trial one ;0. 011 L H2O = IS. Mm/L (4. 9 x 10-4 -e . 0002 mol of distortion) 7. A different student fails to insert the stopper into the flask while determining the available volume of the 125 ml flask. What effect does this error has on the calculated molar volume? Mathematically…...

Microbiology (Lab Report) Closed system growth curve Closed System Growth Curve Lab Report PURPOSE Bacteria grown in a closed system show a specific growth pattern called the growth curve which consists of four phases. The lag phase, which is a period of slow growth; exponential phase, period Of maximum growth; stationary phase, where nutrients become the limiting factor making the growth rate equal to the death rate and the death phase where organisms die faster than they are replaced. It…...

The following sample essay on "Khufu Painting": what tools the artist used and what they mean. Medium The artist used acrylic paint on canvas, it gives the picture a nice clean cut and looks like it was just painted yesterday instead of in the mid !960’s. It was a smart move on the part of the artist because acrylics can dry fast, they are thin, and resistant to cracking when the climate changes and it will also not darken or…...

Melting point temperature is a physical property of pure substances. It is an intensive property, which means the amount of material tested is irrelevant. This lab will determine the melting point temperatures of two known pure substances, naphthalene and p-dishonorable, using micro-sized quantities and a capillary melting tube apparatus. The percent error will then be calculated y comparing the experimental value to the known literature value. Results: In Table 1 on the next page, it shows the literature value melting…...

Materials: 9 test tubes Test tube rack Test tube holder Grease pencil Hot plate 20 ml honey solution 20 ml egg white and water mixture 20 ml corn oil Oats and water 20 ml gelatin and water solution 20 ml potato and water mixture 20 ml apple juice and water mixture 20 ml unknown substance  0 ml unknown substance  Paper towels 600 ml beaker Brown paper Beirut reagent Benedicts solution Iodine solution Procedure:  Place test tubes in the test tube…...

Liquid is usually confined in a container, so its volume is relative to the volume of its container There are various instruments that are used to accurately measure the density of substances; the most commonly used are the densitometers, viscometer and hydrometers [3]. In this experiment, the density of selected liquid samples will be measured using a viscometer. 1. 2 Objectives of the Experiment 1 . To determine the density of low boiling point liquid samples by measuring their mass…...

Lipids are ‘a large and varied group of organic compounds, (3) ‘which are insoluble in water, but soluble in organic solvents such as ethanol and ether.’ (7). The molecules contain atoms of hydrogen, carbon and oxygen. ‘The ratio of hydrogen to oxygen atoms is always greater than 2:1.’ (2)’Triglycerides are fats and oils and are made when glycerol form condensation reactions with three fatty acids to produce ester bonds.’ (2). At 20�C fats are solids whereas oils are liquids. One…...

Lately I’ve been pondering the subject of superheroes. Everyone has their favorite – mine is Batman – and I think everyone at some time has fantasized about being one. I know I have. Of course, unlike Batman, who uses cunning, strength, battle expertise and a bizarre psychological makeup to his advantage, I’m thinking that having superpowers might be one of the prerequisites of the job. Unfortunately, most of the powers that are of interest to me, especially the ability to…...

Kinetic energy, a root of energy stored in cells, causes molecules to hit into each other and move in new directions. Diffusion is the result of this contact. Diffusion is the random movement of molecules to an area of lower concentration from an area of higher concentration. Osmosis is a type of diffusion. This is the diffusion of water through a selectively permeable membrane from a region of higher water potential to a region of lower water likely. Water potential…...

Introduction: Copper(II) iodate(V) ionizes weakly in water: Cu(IO3)2 + aq Cu2+(aq) + 2IO3-(aq) For a saturated solution of copper(II) iodate(V), concentration of IO3- ions doubles that of the Cu2+ (aq) ions, and Ksp of Cu(IO3)2(s) can be calculated by determining the concentration of Cu2+(aq) ion of a saturated Cu(IO3)2(aq). The e. m. f. of a galvanic cell consisting of a Zn(s)/Zn2+(aq) half-cell and another half-cell containing a copper strip in contact with a saturated solution of Cu(IO3)2(aq) is measured by…...

Introduction: The experiment will take place with three conical flasks with the same amount of water in each flask. The three flasks will be different colours, which are black, silver and a clear glass. The experiment will be carried out twice, in one case the factors affecting the rate of cooling will be experimented in the lab and in the other case the factors affecting the rate of cooling will be experimented on the data logging, produced as a graph.…...

Initial hypothesis: A 1 Ox eluted potassium dichloride solution have an expected spectrophotometer reading of 1. 000 while a xx diluted potassium dichloride solution have an expected spectrophotometer reading of 0. 200. The result we obtained correlates strongly to the hypothesis, albeit with a spectrophotometer reading error reaching as high as +0. 07 which is still in the acceptable range. We obtained 1. 066 spectrophotometer reading for our xx diluted potassium dichloride solution and 0. 224 spectrophotometer reading for our…...

In this experiment, you Will investigate the variation in density among three Group AAA elements. You will use your results to predict the density of another Group AAA element. Pre Lab Questions: 1. How are elements arranged in a periodic table? – Atomic number 2. What are the vertical columns in the periodic table called? – Periods 3. What determines whether two elements will have similar chemical properties? If they are in the same group 4. What property will you…...

In this experiment, we aimed to extract caffeine from the tea leaves in the tea bags provided beginning with a lid-liquid extraction method and then a liquid-liquid extraction. Extraction techniques are used to isolate and remove particular compounds form another substance. For both solid-liquid and liquid-liquid extraction techniques, solvents should be chosen by their miscibility in water (should be immiscible), they should have relatively low boiling points for faster and easier extraction, and they should be enervative with the other…...

In this lab, the purpose is to measure whether the changes of substrate concentration will affect the rate of anaerobic respiration. Because the rate of reaction refers to how quickly the reactants are used up or how quickly the products are formed, one method is to measure the volume of gas given off, the more gas given off per time interval results faster reactions. Question: Will the changes in substrate concentration affect the rate of anaerobic reaction? Why or why…...

The following sample essay is about testing the effectiveness of biological control. Read the introduction, body and conclusion of the essay, scroll down. In this experiment, the effectiveness of biological control is tested using lady beetles and aphids. Lady beetles are predacious coelenterate that feed primarily on aphids (order hemisphere). Aphids feed on a plethora of plants including peach, plum, and apricot. Aphids are also vectors of plant disease. Eight replicates were conducted. In each replicate a lady beetle is…...

In the equation, A = BBC where A is the absorbency, a is the specific absorbency, b is the path length, c s concentration. This report presents the procedures for the experiment, the experiment’s results, and an analysis of those results. In this experiment, suspects containing a reagent blank is inserted into the spectrophotometer with the meter adjusted to read zero absorbency. The composition of the reagent blank should be intestinal to that of standard or unknown solutions except for…...

In general, solubility rules can be used to predict the outcome of double replacement reactions. I have come to this decision, because almost all of the data recorded from the lab, with the exception of number 13, agreed with the predictions made beforehand. 2. Out of the 15 combinations, the observations made for the combination of number 13 (the reaction of lead (II) nitrate and barium chloride), did not agree with what was predicted, based on the solubility rules.The solubility…...

In 1835, the French chemist Charles Thilorier was the first man to discover dry ice. One day he opened a very large container of liquid carbon dioxide. The carbon dioxide would quickly evaporate, which left a solid dry ice in the bottom of the container. For the next 60 years, dry ice was observed in university laboratories. Dry ice is a solid form of carbon dioxide. Dry ice changes directly from a solid to a gas. This process is known…...

If the mass of the paper helicopter increases, then the drop time of the paper helicopter will decrease because the paper helicopter with the greater mass will take a longer time to reach terminal velocity ( when there is a balance of forces and thus zero acceleration) which results in a shorter drop time because the object is still accelerating. The mass of the paper helicopter will be measured by using 5 paperclips of each . 7g and the same…...

The following sample essay on experiment by inclined plane and air resistance and friction force. To read the essay's introduction, body and conclusion, scroll down. If the metal trolley is let free down the inclined plane, its move will be accelerated. Later, as the air resistance and friction force have influence on acceleration, they will change it. Analysis: The first part of experiment included preparing an inclined plane. The physics book by Giancoli was laying down on one table, while the other…...

If the boiling points are too close, this method will not work because the two compounds will begin evaporating at close temperatures and will condense down to the receiving flasks at relatively the same times. This will not create an ideal separation. The apparatus used for this type of distillation is longer than that of a simple distillation experiment because this kind of apparatus creates more efficient separation. This happens because the fractional distillation apparatus is longer, and allows for…...

If one can tell if a planet has oxygen on it based on its bright line spectra, research could be done to tell if people can live on the planet or not. This would be a huge advance in science if it was possible to tell if people can live on other planets by knowing the elements on the other planets. This would solve the problem of the world becoming over-populated and would help prevent the spread of disease. Introduction-…...

I then compared the three volume measurements and provided observation. The ext experiment was to determine the effects of salt concentration on bacterial growth. The tubes of broth were labeled as directed and antiseptically inoculated with the appropriate organism, and incubated for 24-rash. After incubation I observed the tubes for the presence or absence of growth. Methods 1. Start with a graduated beaker, or some other container marked at known volume levels. Fill the beaker or measuring cup to 200…...

I did a preliminary experiment to see if my method would work and if there were any problems with the way I will conduct my experiment. Preliminary Results Temperature (i? C) Distanced Bounced (Cm) 90 81 40 68 0 20 Factors affecting my experiment If I use different squash balls of different elasticity it will affect the bounciness of the ball.  If I use different surfaces for the ball to bounce on, I may get different results because different surfaces…...

I concentrated HCI (drops) Discussion Bunsen burner Most chemical synthesis involves separation and purification of the desired product from unwanted side products. Some methods of separation, such as filtration, sedimentation, declaration, extraction, and sublimation were discussed earlier. This experiment is designed as a quantitative evaluation of your individual laboratory skills in carrying out some of these operations. At the same time you will become more acquainted faith two fundamental types of chemical reactions redo reactions and metathesis (double-displacement) sections. By…...

I have been asked to investigate the link between colour and heat loss. Does the silver or the black cup lose its heat faster? HYPOTHESIS I think that the silver cup will retain the heat for a longer period of time than the black cup, I think this because the black cup will absorb the heat, where as the silver cup will reflect the heat back into the cup causing the black cup to cool down faster than the silver…...

Hess’ Law of Heat Summation Hess’ Law states that: “The enthalpy change for any reaction depends  on the products and reactants and is independent  of the pathway or the number of steps between  the reactant and product”. BASICALLY:    Hess’ Law states “the heat evolved or absorbed in     a chemical process is the same whether the process     takes place in one or in several steps”     ­­;This is also known as the “law of constant heat summation”. All it means is that no matter how many steps the chemical     reaction proceeds through, the total heat evolved or absorbed    is the added heat values of each step and will always be    a constant figure for that process. For example:     When phosphoric acid (a tri­hydrogen acid) is neutralized     with a base, the hydrogens are neutralised in 3 steps:    STEP 1:   H3P04 + NaOH ­; NaH2PO4 + H2O ­gives X amount of heat     STEP 2:   NaH2PO4 + NaOH ­; Na2HPO4 + H2O ­gives Y amount of heat    STEP 3:   Na2PO4 + NaOH ­; Na3PO4 +H2O ­gives Z amount of heat    Therefore, the total heat of reaction (   Hrxn) is equal to: Law Of Constant Heat Summation There are two (2) ways to calculate the heat of reaction  using Hess’ Law: 1­  Equation Method (Algebraic Method) 2­  Heat of Formation Method (Summation Method) Equation (Algebraic) Method Strategy:    ­add equations for reactions with known enthalpies     so that their net result is the desired reaction Sample Problem 1: Use the equations below to determine the enthalpy of reaction for the decomposition of hydrogen peroxide: H2O2(l)         H2O(l)    +    1/2 O2(g) The equations are: 1­    H2(g)   +   O2(g)       H2O2(l)    2­    H2(g)   +   1/2 O2(g)      H2O(l) Hf = ­188 kJ Hf = ­286 kJ Solution: Sample Problem 2: Use the following equations: 1­    1/2 N2(g)   +   3/2 H2(g)       NH3(g) 2­    1/2 N2(g)   +   O2(g)     NO2(g) 3­    H2(g)   +   1/2 O2(g)     H2O(g) Hf = ­46. 0 kJ Hf = +34. 0 kJ Hf = ­242. 0 kJ to calculate the enthalpy of reaction for: 4 NH3(g)   +   7 O2(g)        4 NO2(g)   +   6 H2O(g) Solution: Practice Problem: Calculate the heat of reaction for the oxidation of one mole of ethanol to ethanoic acid: C2H5OH(l)   +   O2(g)         CH3COOH(l)   +   H2O(l) Use the equations below: ­    C2H5OH(l)   +   3 O2(g)          2 CO2(g)   +   3 H2O(l) 2­    CH3COOH(l)   +   2 O2(g)         2 CO2(g)   +   2 H2O(l) Hc = ­1367 kJ Hc = ­874 kJ Enthalpy of Formation  (Summation) Method Standard Molar Enthalpy of Formation: (             ) ­the amount of ____ (absorbed or released) when _________ of   a compound is formed from its _________________ in their  standard states ­most enthalpies of formation are ­ve (__________________)? therefore, most compounds are ___________ stable than the  elements they are made from…...