Polymerization of ε-Caprolactone and Analysis of Variable Length Polymers by Destructive Testing (12/13/13)
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Abstract
The purpose of this lab was to find out how adjusting the amount of catalyst and initiator in a polymer can affect the properties of the polymer. For example, if a polymer has a longer chain length as a result of less initiator, will it hold up better to direct force? To do this we made polymers with different monomer to initiator to catalyst ratios. We put these polymers into differently shaped molds and tested them to see how they stood up to direct impacts and suspended weight. The results from the direct impact test were extremely varied and did not show any correlation. The results from the suspended weight test showed that, generally, the polymers with a higher monomer to initiator to catalyst ratio (meaning longer molecular strands) were able to suspend more weight without breaking. This means that if somebody wanted to build an object that had to suspend weight, they would want to make it out of a polymer with long chains.
The purpose of this lab was to find out how adjusting the amount of catalyst and initiator in a polymer can affect the properties of the polymer. For example, if a polymer has a longer chain length as a result of less initiator, will it hold up better to direct force? To do this we made polymers with different monomer to initiator to catalyst ratios. We put these polymers into differently shaped molds and tested them to see how they stood up to direct impacts and suspended weight. The results from the direct impact test were extremely varied and did not show any correlation. The results from the suspended weight test showed that, generally, the polymers with a higher monomer to initiator to catalyst ratio (meaning longer molecular strands) were able to suspend more weight without breaking. This means that if somebody wanted to build an object that had to suspend weight, they would want to make it out of a polymer with long chains.
Inquiry into Bonding (11/18/13)
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Introduction:
The purpose of this lab was to use physical properties such as electrical conductivity, structure, and melting point to determine whether unknown compounds were held together by ionic or covalent bonds. To do this, we put the unknown substances through a series of tests to see which bond they behaved most like.
Atoms lose or gain electrons because they want to have a full outer ring of electrons. When an atom has a full outer shell, it is said to have a full octet. When an atom has a full octet, it is in a very stable state. This is why the noble gases don’t react with other elements; they have a full octet and are therefore extremely stable.
The purpose of this lab was to use physical properties such as electrical conductivity, structure, and melting point to determine whether unknown compounds were held together by ionic or covalent bonds. To do this, we put the unknown substances through a series of tests to see which bond they behaved most like.
Atoms lose or gain electrons because they want to have a full outer ring of electrons. When an atom has a full outer shell, it is said to have a full octet. When an atom has a full octet, it is in a very stable state. This is why the noble gases don’t react with other elements; they have a full octet and are therefore extremely stable.
Spectroscopic Investigation of Metals in Solution (10/17/13)
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Introduction:
The purpose of this lab was to use spectroscopy to determine what element unknown substances were. Spectroscopy is the use of the knowledge of what frequency photons, or light particles, a certain element emits to identify an element. To understand this we must first know what an atom looks like. The Bohr model most easily represents an atom, but there are newer models that give a more accurate representation of the atom. The Bohr model of the atom is a cluster of spherical protons and neutrons in the center as the nucleus and is surrounded by rings that contain the electrons. The electrons are smaller than the protons and neutrons and orbit the nucleus on certain levels. The quantum mechanical model of the atom is the new and improved version of the Bohr model. Instead of representing electrons as specific particles, this model represents them as clouds of where the electron will most likely be. There are four different kinds of electron clouds. The different clouds are represented by the letters s, f, d, and p. Each of these different clouds has a different energy level, in addition to the original energy levels. For example, an electron on the level 1f would have more energy than an electron on the level 1s. This model is more accurate because we now know that electrons are point particles, meaning they have no volume and exist in the first dimension, and that it is impossible to know exactly where the electrons are. While this model is more accurate, it is more practical to use the Bohr model when first learning about the atom because it makes the learning simpler and easier to grasp initially.
The purpose of this lab was to use spectroscopy to determine what element unknown substances were. Spectroscopy is the use of the knowledge of what frequency photons, or light particles, a certain element emits to identify an element. To understand this we must first know what an atom looks like. The Bohr model most easily represents an atom, but there are newer models that give a more accurate representation of the atom. The Bohr model of the atom is a cluster of spherical protons and neutrons in the center as the nucleus and is surrounded by rings that contain the electrons. The electrons are smaller than the protons and neutrons and orbit the nucleus on certain levels. The quantum mechanical model of the atom is the new and improved version of the Bohr model. Instead of representing electrons as specific particles, this model represents them as clouds of where the electron will most likely be. There are four different kinds of electron clouds. The different clouds are represented by the letters s, f, d, and p. Each of these different clouds has a different energy level, in addition to the original energy levels. For example, an electron on the level 1f would have more energy than an electron on the level 1s. This model is more accurate because we now know that electrons are point particles, meaning they have no volume and exist in the first dimension, and that it is impossible to know exactly where the electrons are. While this model is more accurate, it is more practical to use the Bohr model when first learning about the atom because it makes the learning simpler and easier to grasp initially.
Determining the Density of Carbon Dioxide (CO2) (9/18/13)
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Introduction
When an Alka-Seltzer tablet(3NaHCO3(s)+H3C6H5O7(s)) is added to water(H2O(l)), a chemical reaction occurs. The result of this chemical reaction is one molecule of sodium citrate dissolved in water(Na3C6H5O7(aq)), four molecules of water(4H2O(l)), and three molecules of carbon dioxide gas(3CO2(g)).
The density of a pure substance will always be the same, no matter what size or shape it is in. You may think that 50 grams of carbon dioxide will have less density than 500 grams of grams of carbon dioxide, simply because it has more mass. But the volume increases proportionally with the mass so that the density always stays the same at 0.00196 g/ml.
When an Alka-Seltzer tablet(3NaHCO3(s)+H3C6H5O7(s)) is added to water(H2O(l)), a chemical reaction occurs. The result of this chemical reaction is one molecule of sodium citrate dissolved in water(Na3C6H5O7(aq)), four molecules of water(4H2O(l)), and three molecules of carbon dioxide gas(3CO2(g)).
The density of a pure substance will always be the same, no matter what size or shape it is in. You may think that 50 grams of carbon dioxide will have less density than 500 grams of grams of carbon dioxide, simply because it has more mass. But the volume increases proportionally with the mass so that the density always stays the same at 0.00196 g/ml.