Thermal decomposition Thermal decomposition of a compound to yield a deposit of the stable residue is called pyrolysis. In this a stable residue is deposited over a substrate by thermal decomposition and reaction of compounds. Organic-metallic compounds decompose at low temperature (< 600˚C) where as metal halides decomposes above 600˚ C to yield metallic deposits. Many of the organic silicates can be thermally decomposed to give substantially pure SiO2 films of dielectric properties close to those of silica. This is usually accomplished by passing an inert carrier gas carrying vapour from the silicates over heated substrates. For example
Si (OC2H5)4 decomposes to SiO2 + 4C2H4 + 2H2O -------------- (3.8)
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In some cases Oxygen is also introduced as a reactant carrier to control the characteristics of the film.
B. Vapour phase reaction Constituent species in the gaseous phase react in the presence of inert, oxidizing or even some reducing atmosphere to form the desired product. Thus SiO2 films can be produced by the reaction of SiCl4 vapour with carbon dioxide in the pressure of hydrogen gas and this is known as Philips process. The reaction goes in the following way
SiCl4 + CO2 + H2 SiO2 + CCl4 + H2 --------------- (3.9) SnO2 films often used as metal oxide resistors can be prepared from SnCl4 vapours in presence of water and HCl vapours at a temperature about 500˚C and the reaction can be represented by the equation
SnCl4 + 2H2O + HCl SnO2 + 4HCl + HCl ---------------
Discussion 1. Zn0 (s)+ Cu2+S6+O42-(aq) →Cu0(s) + Zn2+S6+O42-(aq) Zn0(s) → Zn2+(aq) + 2e- Cu2+(aq) + 2e- → Cu0(s) Zn0(s) + Cu2+(aq) → Zn2+(aq) + Cu0(s) Oxidant (oxidizing agent) is the element which reduces in experiment.
Tyler White CHEM151LL 32658 04/01/2018 Different Types Chemical Reaction Types and Equations Purpose: The purpose of this lab experiment is to examine different types of chemical reactions such as Decomposition reaction, Synthesis reactions, Combustion reactions, and different Chemical equations. The experiments were conducted online using Late Nite Labs. Materials: Because the experiments were conducted online there wasn’t any physical use of materials, only digital ones, for these labs to be performed. Only the registration for the website was needed to perform these online labs, as well as a desktop computer.
Genetic engineering is changing the DNA code to express different traits. A plasmid is a circular piece of DNA that contains important genetic information. Recombinant DNA is the product after inserting your desired genes. The genes we hoped to insert in the pGLO lab were the GFP gene and the ampicillin resistance gene. GFP was needed so that we would tell if the ampicillin resistance gene had been properly placed when the bacteria glowed under a UV light.
1.0 Introduction Oxalates which refer to any salt or ester of oxalic acid are common constituents of plants and are found in the majority of plant families. They occur either as free acids, soluble salts of potassium, sodium and magnesium and the insoluble salt of calcium. The amount of oxalates in plants ranges from a few percent of dry weight to up to 80% of the total weight of plants. (Garcia-Fernandez et al., 2014) The amount of oxalates in plants ranges from a few percent of dry weight to up to 80% of the total weight of the plant.
Hypothesis: Increasing substrate concentration will increase the initial reaction rate until it stops increasing and flattens out. Independent Variable: Substrate concentration Dependent Variable: The substrate itself, 1.0% Hydrogen Peroxide How Dependent Variable will be Measured: Hydrogen Peroxide will be used in every experiment, just with different test tubes. The amount of Hydrogen Peroxide in the mixing table is the amount that will be added to each test tube.
Pop Rocks and soda have a very interesting chemical reaction with each other. Soda is a very pressurized drink that has carbon dioxide in it. Carbon dioxide is a pressurized chemical. When it is shaken, it fizzes, and causes pressure, and overflows releasing the carbon dioxide. It is similar to the Pop Rocks.
Introduction: The purpose of this experiment is to demonstrate the different types of chemical reactions, those including Copper. There are different types of chemical reactions. A double displacement reaction is a chemical process involving the exchange of bonds between two reacting chemical species. A a decomposition reaction is the separation of a chemical compound into elements or simpler compounds and the single-displacement reaction is a type of
The results do not support the hypothesis that a higher surface area to volume ratio would result in sulphuric acid being diffused into the agar cubes in the shortest amount of time. This is evident in the results as the exact opposite to what was predicted occurred. Instead of the smallest cube with the largest surface area to volume ratio of 1cm3 having the quickest diffusion rate, it conversely took the longest at 0.092 cm3 per second, whilst the 2cm3 cube with 0.0384 cm3 per second took the least amount of time. This directly refutes the hypothesis. There was also no consistent trend evident in the results.
Lab Report Experiment 6 Rates of Chemical Reactions By Nikhola Mirashirova Lab Partner: Dina Abetova Section 3, Saturday October 31, 2015 Introduction Rate reaction is the measure of the change in concentration of the reactants or the change in concentration of the products per unit time.1,2 Rate law for this experiment: Rate = k(I-)m(BrO3-)n(H+)p There are several factors which affect the rate of reaction: catalyst, reactant concentration, and temperature.1,2 A catalyst is a substance that changes, increases or decreases, the rate of a chemical reaction but is not being used up during the reaction.3 It provides an alternative way, so that the rate of reaction changes.4 Catalyst, which is used in this experiment, is (NH4)2MoO (0.5 M).
Title: THE BALLOON INFLATION REACTION Introduction: Chemistry is one thing that makes us understand and gives us reasons of why certain reactions gives certain results. In this experiment we will be illustrating the reaction between baking powder and vinegar and see what happens to the balloon that is attached to it. Hypothetically the reaction of the vinegar and baking powder will produce carbon dioxide which will inflate the balloon. If the more vinegar may happen that when more vinegar is added to the baking powder it may produce more carbon dioxide thus the balloons diameter increases.
Jaspreet Singh Professor Paratore Biology 1 November 1, 2014 Spectrophotometry Identifying Solutes and Determining Their Concentration Statement of the Exercise or of the Problem The purpose of the lab experiment was to attain the following objectives: • Learning to Operate the Spectrophotometer • Construct absorption spectra for cobalt chloride and chlorophyll. Hypothesis If greater and higher concentrations of cobalt chloride are added to each solution then greater amounts of light would be absorbed by each solution. Thus a liner relationship will result in which the absorbance of a substance would be proportional to its concentration, which will be depicted, in a linear graph.
1. 150 ml of boiled water was poured into each of the three beakers labeled A, B, C. 2. Five tea bags were soaked for the time given by the manufacturer (two minutes) , in beaker A (Control). The teabags were immediately removed after the time elapsed. 3.
Properties of Ionic and Covalent Substances Lab Report Introduction The purpose of this lab was to determine which of the following substances: wax, sugar, and salt, are an ionic compound and which are a covalent compound. In order to accurately digest the experiments results, research of definitions of each relating led to the following information: ionic compounds are positive and negatively charged ions that experience attraction to each other and pull together in a cluster of ionic bonds; they are the strongest compound, are separated in high temperatures, and can be separated by polar water molecules. A covalent compound forms when two or more nonmetal atoms share valence electrons; covalent compounds are also
Aim: To find out the relationship between the greater concentration of sodium thiosulfate when mixed with hydrochloric acid and the time it takes for the reaction (the time it takes for the solution to turn cloudy) to take place and to show the effect on the rate of reaction when the concentration of one of the reactants change. Introduction: The theory of this experiment is that sodium thiosulfate and hydrochloric acid reach together to produce sulfur as one of its products. Sulfur is a yellow precipitate so, the solution will turn to yellow color while the reaction is occurring and it will continue until it will slowly turn completely opaque. The reaction of the experiment happens with this formula: “Na2 S2 O3 + HCL =
Joshua Miller 12/18/17 Fermentation Lab report Introduction The term fermentation refers to the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat (wikipedia). Sugars are converted to ethyl alcohol when fermentation happens. In this experiment we determined if yeast cells undergo fermentation when placed in a closed flask with no oxygen. Glucose and yeast are mixed together in a closed flask and allowed to incubate for about one hour.