«The objective of this experiment is to determine the total concentration of metal ions required to completely react with EDTA, or ethylene diamine tetra-acetate. The concentration determined will then be taken as the equivalent concentration of...» Document abstract
$3.95
4 word format
Language : english
physics & chemistry
course material
date published
15/04/2008
review : not yet assessed
level : Advanced
requested 0 times
SummaryThe objective of this experiment is to determine the total concentration of metal ions required to completely react with EDTA, or ethylene diamine tetra-acetate. The concentration determined will then be taken as the equivalent concentration of Ca2+ and Mg2+. Ca2+ will be analyzed separately in an additional titration after Mg(OH)2 has been precipitated from the solution using a strong base.
«From the age of twelve and older nearly 40% of our country, about 98 million Americans, has used Cannabis sativa for its psychological and physiological effects in much the same way as it has been throughout recorded history (AMA Council). This...» Document abstract
$3.95
4 word format
Language : english
physics & chemistry
school essay
date published
04/12/2007
review : not yet assessed
level : General public
requested 2 times
SummaryFrom the age of twelve and older nearly 40% of our country, about 98 million Americans, has used Cannabis sativa for its psychological and physiological effects in much the same way as it has been throughout recorded history (AMA Council). This lengthy past has constructed a harsh stigma around the plant and those who smoke it, sparking demonstrations, laws and cult classic anti-drug films. As modern science begins to understand how to apply its effects to medicine, this stigma persists. This conjured cloud of misunderstandings and myths confuses the issue, effectively hiding what medicine has already decided; Cannabis has a significant possibility to relief suffering for many different patients.
«Chromatography is a technique used to separate and analyze chemicals. It was initially discovered in the early 1900’s by chemist Mikhail Tsvett who was researching chlorophyll to separate plant pigments.1 The components undergoing separation are...» Document abstract
$3.95
4 word format
Language : english
physics & chemistry
case study
date published
20/11/2007
review : not yet assessed
level : General public
requested 1 times
SummaryChromatography is a technique used to separate and analyze chemicals. It was initially discovered in the early 1900’s by chemist Mikhail Tsvett who was researching chlorophyll to separate plant pigments.1 The components undergoing separation are divided into two phases, a stationary phase, and a mobile phase. The stationary phase does not move while the mobile phase, which includes the sample, passes through the stationary phase. Different chemicals are impeded at different rates through the stationary phase based on individual properties which make them unique.2
«The blade of a turbine is tilted an angle.
Movement of the air is channeled creating low and high pressures on the blade that force it to move.
The blade is connected to a shaft which in turn is connected to an electrical generator.
The...» Document abstract
$9.95
10 slides .ppt
Language : english
physics & chemistry
presentation
date published
13/11/2007
review : not yet assessed
level : General public
requested 4 times
SummaryThe blade of a turbine is tilted an angle.
Movement of the air is channeled creating low and high pressures on the blade that force it to move.
The blade is connected to a shaft which in turn is connected to an electrical generator.
The mechanical energy of the turning blades is changed into electricity.
Wind speeds typically must be sustained at least 10 mph to turn larger turbines fast enough to generate electricity
«LSD, the common abbreviation for Lysergic Acid Diethylamide-25, often termed “acid” in the streets, is one of the most potent hallucinogenic substances known to man. The chemical was actually synthesized for the first time in 1938 by a German...» Document abstract
$2.95
3 word format
Language : english
physics & chemistry
school essay
date published
23/10/2007
review : not yet assessed
level : General public
requested 5 times
SummaryLSD, the common abbreviation for Lysergic Acid Diethylamide-25, often termed “acid” in the streets, is one of the most potent hallucinogenic substances known to man. The chemical was actually synthesized for the first time in 1938 by a German scientist named Albert Hoffman. However, in that year, Hoffman did not see any use for the chemical, and so it was scrapped into the “useless” pile. It was not until 1943 that Hoffman decided to pick up on the research of the molecule again. While working with it, he happened to either inhale or ingest some of it accidentally, and went through a truly novel experience. Since then, new more efficient ways to synthesize the chemical have been developed for further study.
«As living things, we are highly sensitive to changes in our environment; this doesn’t only mean changes outside our body, but changes from within also. For the cells in our bodies to function properly a certain temperature and pH has to be...» Document abstract
$1.95
2 word format
Language : english
physics & chemistry
case study
date published
09/10/2007
review : not yet assessed
level : General public
requested 5 times
SummaryAs living things, we are highly sensitive to changes in our environment; this doesn’t only mean changes outside our body, but changes from within also. For the cells in our bodies to function properly a certain temperature and pH has to be maintained. Even a slight change in pH inside our bodies can cause serious repercussions. Most of the fluids in our bodies range in pH from 6 to 8. Our body has buffers that maintain the pH of blood very close to 7.4 and we can not survive for more than a few minutes even the blood pH has changed slightly. Nature, to make sure homeostasis is maintained, has provided certain molecules that act as buffers. Buffers are molecules that absorb or release protons depending if the solution becomes more acidic (absorbs protons) or more basic (releases protons) (Miyazaki 4).
«The purpose of this lab is as follows: To use mole ratios to predict the amount of precipitate formed, to use mole ratios to study the effect of reactant molarity on the yield of product, to use mole ratios to study limiting and excess reactants,...» Document abstract
$3.95
4 word format
Language : english
physics & chemistry
case study
date published
26/09/2007
review : not yet assessed
level : General public
requested 4 times
SummaryThe purpose of this lab is as follows: To use mole ratios to predict the amount of precipitate formed, to use mole ratios to study the effect of reactant molarity on the yield of product, to use mole ratios to study limiting and excess reactants, and to design an experiment which achieves the above objectives.
The exact reacting ratio has to come into play when the two solutions are mixed. The molarity of the solution given must calculated before the experimentation process begins. One of the reactants will stay the same and the other one will change. This reactant will change in volume, thus being the independent variable. There will be a precipitate forming from the reaction of the two reactants. The molarity of the changing reactant is to be calculated. To do this, the concept of the exact reacting ratio should be comprehended. When two solutions are mixed and the ratio of their moles is perfect, this will be the exact reacting ratio. But when the ratio is not perfect (which in most cases it will not be) then one of the chemicals will be left over. It will not be fully used. The reactant that is fully used is called the limiting reacting because it is limiting the other reactant from fully reacting. The reactant that is not fully used up is the excess reactant. This one is left over. These concepts could be more easily grasped and understood through an example. How many hamburgers can you make with 8 buns and 5 pieces of meat? Only 5. In this case, the buns are the excess reactant because they will not be used up; the meat is the limiting reactant.
The exact reacting ratio has to come into play when the two solutions are mixed. The molarity of the solution given must calculated before the experimentation process begins. One of the reactants will stay the same and the other one will change. This reactant will change in volume, thus being the independent variable. There will be a precipitate forming from the reaction of the two reactants. The molarity of the changing reactant is to be calculated. To do this, the concept of the exact reacting ratio should be comprehended. When two solutions are mixed and the ratio of their moles is perfect, this will be the exact reacting ratio. But when the ratio is not perfect (which in most cases it will not be) then one of the chemicals will be left over. It will not be fully used. The reactant that is fully used is called the limiting reacting because it is limiting the other reactant from fully reacting. The reactant that is not fully used up is the excess reactant. This one is left over. These concepts could be more easily grasped and understood through an example. How many hamburgers can you make with 8 buns and 5 pieces of meat? Only 5. In this case, the buns are the excess reactant because they will not be used up; the meat is the limiting reactant.
«The purpose of this lab was to find out the indications of chemical changes and reactions when mixing two different substances, which are listed specifically in the Observations section. The purpose is also to find out how a percent by mass solution...» Document abstract
$5.95
6 word format
Language : english
physics & chemistry
case study
date published
26/09/2007
review : not yet assessed
level : General public
requested 1 times
SummaryThe purpose of this lab was to find out the indications of chemical changes and reactions when mixing two different substances, which are listed specifically in the Observations section. The purpose is also to find out how a percent by mass solution is made up. The data and observations that is recorded will help find out the indications of chemical changes and reactions. Since this is a very big part of the lab, it is imperative to take detailed notes and observations. Besides recording data, it is necessary to know how to calculate it. It will be needed to find out how a percent by mass solution is made up. It is also very important to have a good method of approach towards calculating this data because this is what drives the whole lab. Without the percent by mass solution calculations, we would not be able to make up the chemical solutions.
«In "Ferromagnetism and the Curie-Weiss Law" the author will start by giving a more complete derivation of the Curie-Weiss law,
which might make a few points clearer. Then he will try to address some of your
questions more directly. The author...» Document abstract
$2.95
3 pdf format
Language : english
physics & chemistry
course material
date published
25/06/2007
review : not yet assessed
level : Advanced
requested 46 times
SummaryIn "Ferromagnetism and the Curie-Weiss Law" the author will start by giving a more complete derivation of the Curie-Weiss law,
which might make a few points clearer. Then he will try to address some of your
questions more directly. The author hopes that the derivation itself will make things
clearer.
«In "Position of the Fermi Level for Extrinsic Semiconductors" the author will talk a little more in detail about doped semiconductors. Here, the author answers the following questions:
(i) What is the position of the Fermi level for an extrinsic...» Document abstract
$1.95
2 pdf format
Language : english
physics & chemistry
course material
date published
25/06/2007
review : not yet assessed
level : Advanced
requested 20 times
SummaryIn "Position of the Fermi Level for Extrinsic Semiconductors" the author will talk a little more in detail about doped semiconductors. Here, the author answers the following questions:
(i) What is the position of the Fermi level for an extrinsic semiconductor?
(ii) What is the concentration of electrons(holes) in the conduction(valence)
band?
knowledge network
Sort by
Results 1 - 10 out of a total of 11
Subject :
Type :
Extension :
Language :
Size :
Document>physics & chemistry