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, definitions of each relating factor were researched, leading 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 is formed when two or more nonmetal atoms share valence electrons; covalent compounds are also categorized into two sections: polar covalent and nonpolar covalent. Furthermore, polar covalent compounds dissolve in water, while nonpolar covalent compounds do not. Dissolving is the process in which a solvent and a solute interact with each other and form a solution.
Wait for substance to adjust to room temperature before use. Container, the container affects the surface area and the number of particles that are exposed to each other The thinner the container the slower the reaction as there are less particles which the substances can collide with. Use the same sized container for every experiment
The iotas of materials with covalent bonds are bound firmly to each other in stable atoms, yet, they are for the most part not extremely pulled in to different particles in or around the material. Carbon-Carbon bonds (C-C) are covalent bonds and frame the premise of generally biomolecules. Monosaccharides, for example, glucose, fructose and galactose are held together by a kind of covalent bond known as a glycosidic bond. When they are associated together, they can shape bigger starches. Two monosaccharides connected together frame a disaccharide.
Repeat steps 1-10 for two more trials. Conclusion: 1. I chose to compare temperature and amount of reactants in my experiments. I chose these because I thought they would reveal the the most drastic time differences. I also chose these factors because I had prior knowledge of them before I even started chemistry.
Firstly, unknown B has a low melting point, a prominent characteristic among covalent compounds. This is due to the attraction between the atoms not being as reinforced as an ionic compound, thus it takes less energy to separate. In addition, unknown B has a very low solubility and conductivity, this is due to the atoms sharing electrons, therefore they cannot have the ability to separate and form an ion. However, it should be noted that covalent compounds should most definitely not be conductive or soluble, but the results have shown otherwise, thus it should be concluded that there may have been contamination between the scoopula’s used. Conclusion All in all, the experiment has provided much insight into the topic of ionic and covalent bonds regarding compounds.
What supports this possibility was the fact the product was unable to be 100% dried. This resulted in a material that was more like slightly wet clay then a solid crystal and possibly contain petroleum ether which would result in a lower melting point. Another possible reason was the final product was not, in fact, triphenylmethanol, un pure or
They tested how the temperature would affect the rate of reaction. This was observed by the amount of time it took for the solution to change colors. For many chemical reactions there is an optimum temperature at which the chemicals will react with each other. As was found in their experiment, the temperature affected the rate of reaction. (Deoudes, 2010).
I. INTRODUCTION Different compounds can be classified based on the various chemical and physical properties such as solubility, conductivity, and melting point. Most of the chemical substances have unique features that allows sorting them to ionic, molecular, macromolecular and metallic compounds. Significantly, compounds divides into polar and non-polar, which can be checked by testing with polar and non-polar solvents. Electrical resistance related to the ability of the substance conduct electricity.
The most important aspect of determining the results is the timing. The timing will be used with a stopwatch, and will be timed from the moment that all the solution have been combined, and will end at the point that the solution has completely finished changing colors. In order to add the solution, and start the timer at the same time, I will need a second person to time while I combine the solutions together. In order to maintain similar results, I will also need to keep the same person keeping track as they will start and end the timer at the same time when they see fit in all the reactions. Procedure Reaction 1 Solution A (in a 100 mL graduated cylinder) 10 mL of 2.0M of sulphuric acid 10 mL of 3% hydrogen peroxide 80 mL water Solution B (in a 100mL graduated cylinder) Solution of .04 grams of sodium thiosulfate pentahydrate in 20 mL of water Solution of .9 grams of potassium iodide in 5 mL of water 4 mL starch solution 71 mL of water Combine the solutions in a flask and stir (hand or magnetic stirrer) until turns dark blue Immediately start timing at the moment that the solutions combine together Observation Table (sample data) Experiment 1: Hydrogen Peroxide (mL) Time (seconds) 1
Determination of the Heat Exchanged in Chemical Reactions Introduction: Calorimetry is the science of determining heat and energy exchange in various situations and reactions. It is used for many things everyday including solid and liquid fuel testing, waste disposal, and explosive testing. In our lab, we will are applying calorimetry to determine the change in enthalpy of a weak acid-strong base reaction. My beginning question was: How can we apply Hess’ law and calorimetry to chemical equations to determine the heat exchanged in a reaction? We started by putting 100 mL of water into a coffee cup calorimeter (a polystyrene cup inside another polystyrene cup as an insulator), a magnetic stir bar was added and using the program LabProTM the