Paragraph 1: Compare and Contrast the crystal structures and crystal chemistry of Quartz α-FePO4 and β-FePO4.
The research paper discusses the inversion of quartz type FePO4 from α-FePO4 to β-FePO4 along the temperature range 294K to 1073K.
We first take a look at the difference in lattice and space symmetry between the
2 polymorphs, α-FePO4 and β-FePO4. α-FePO4 is of the space group P3121, with a space group number 152. It has a trigonal lattice symmetry. β-FePO4 is of the space group P6422, with a space group number 181. It has a hexagonal lattice symmetry. Next, we analyse the similarities in crystal chemistry between α-FePO4 and β-
FePO4. To do so, we have to first understand how other quartz homeotypes like
SiO2 are able to have the same structure even though their chemical composition
is
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We look at the cations in SiO2 and FePO4, as anions within these two homeotypes are similar. We find out that SiO2 contains the cation Si4+
(tetravalent), while FePO4 contains the cations Fe3+ (Trivalent) and
P5+(pentavalent). As such, we are able to construct an alter-bound equation of
Fe3+ + P5+ ! 2 Si4+ whereby total charge on either end of the equation is 8+ and total species on both sides of the equation is 2.
Lastly, we focus on the transition from α-FePO4 to β-FePO4 with changes in temperature. At low temperatures from 294K to 969K, FePO4 exists as a α polymorph. At 980K, first order transition occurs, as inter-tetrahedral and tilt angles decreases at an increasing rate as temperature increases from
This paper describes the methods used in the identification, investigation of properties, and synthesis of an unknown compound. The compound was identified as calcium nitrate by a variety of tests. When the compound was received, it was already known to be one of twelve possible ionic compounds. The flame test identified the presence of the calcium anion in the compound. The compound tested positive for the nitrate cation using the iron sulfate test. At this point it was hypothesized that the compound was calcium nitrate. Reactivity tests and quantitative analysis comparing the unknown compound with calcium nitrate supported this hypothesis. Synthesis reactions were then carried out and analyzed.
Physical Chemistry Laboratory Manual, Physical Chemistry Laboratory, Department of Chemistry, University of Kentucky, Spring 2006.
Scibd. N.p. Web. 17 Mar 2014. Beller, Michele.
The mass of Mg + the mass of O2=mass of MgxOx. Knowing the mass of
David and John Free. (26 Nov 2006). MadSci Network: Chemistry. Retrieved on March 6, 2011, from http://www.madsci.org/posts/archives/2007-02/1171045656.Ch.r.html
Snyder, Zack, dir. 300. Prod. Gianni Nunnari, Bernie Goldman, Mark Canton, and Jeffrey Silver. 2007. Warner Bros, 2007. DVD.
Chemistry is not used only in a lab environment, but it is used for every aspect of life. One way to look into a more in-depth view of chemistry is to apply it to a hobby, or something that may personally affect your everyday life. One of the biggest parts of my life and my main hobby is flying. Ever since I was little, I have always wanted to become a pilot. I am currently working towards my private pilot’s license and I am also attending the U.S. Air Force Academy starting in June to study aeronautical engineering. Since flying is such a large aspect of my life and is important to me, I wanted to break it down into an aspect of chemistry. I chose this topic because flying is very important to me and it will continue to be a large part of my life as it will end up being my career in the Air Force. Not only will researching the topic of aviation fuel help me to become a more knowledgeable pilot, but it will also help me to understand more about chemistry and expand on the concepts we have learned this semester. Chemistry is extremely important to planes and pilots. One of the most obvious aspects of flying that deals directly with chemistry is fuel. Without fuel, aircraft would not be able to run. The molecular formula of fuel and the combustion of fuel are just some parts that play into how fuel makes an aircraft run.
Femicide is defined as the act of killing a female simply because she is female. Acts of femicide includes “honor killings,” “dowry deaths,” genital mutilation, rape in war and victimization o female refugees. The treatment of women prisoners and detained immigrant women are also related to the issue of femicide. Essentially, femicide is a form of gender-based violence (Stuart van Wormer & Bartollas, 2011). It is considered to be an extreme form of gender-based violence that may include torture, mutilation, cruelty and sexual violence. The violence often culminated to murder. This violence is linked to gender concepts like inequality, discrimination and disempowerment (Femicide, 2008). It is also viewed as “a form of terrorism that functions to define gender lines, enact and bolster male dominance, and to render women chronically and profoundly unsafe” (Suarez, 2009). Based on international federal and state law, women have the right to be free from violence. Overall, acts of femecide are viewed as a violation of the human rights of women (Femicide, 2008).
In the reaction, potassium peroxodisulphate and potassium iodide will be used to provide the peroxodisulphate ions and iodide ions respectively. The ionic formula for the reaction is as follows:
Schreuder, Jolanda A. H.; Roelen, Corné A. M.; van Zweeden, Nely F.; Jongsma, Dianne; van der Klink, Jac J. L.; Groothoff, Johan W.
23. S. Alwarappan, S. Boyapalle, A. Kumar, C.-Z. Li and S. Mohapatra, J. Phys. Chem. C, 2012, 116, 6556–6559
Many companies all over the world produce chemicals for their products that are harmful to the environment, human health, and to all living species. Green Chemistry is the use of chemistry for the prevention of chemical pollution to the environment by using chemicals that are benign, or not harmful. The Environmental Protection Agency (EPA) states that the mission of Green Chemistry is, “To promote innovative chemical technologies that reduce or eliminate the use or generation of hazardous substances in the design, manufacture, and use of chemical products.” Green Chemistry contains any aspects and types of chemical processes that reduce the negative effects of certain chemicals, in a way, using chemistry to fight chemistry.
Figure 1: The hexacyanoferrate iron (III) ion: contains 6 ligands which are bound to the central metal therefore has a coordination number of 6 (n=6¬). (Hussain,2007) [13]
Ionic compounds, when in the solid state, can be described as ionic lattices whose shapes are dictated by the need to place oppositely charged ions close to each other and similarly charged ions as far apart as possible. Though there is some structural diversity in ionic compounds, covalent compounds present us with a world of structural possibilities. From simple linear molecules like H2 to complex chains of atoms like butane (CH3CH2CH2CH3), covalent molecules can take on many shapes. To help decide which shape a polyatomic molecule might prefer we will use Valence Shell Electron Pair Repulsion theory (VSEPR). VSEPR states that electrons like to stay as far away from one another as possible to provide the lowest energy (i.e. most stable) structure for any bonding arrangement. In this way, VSEPR is a powerful tool for predicting the geometries of covalent molecules.