NOMENCLATURE OF IONIC COMPOUNDS CHEMISTRY 1405
... Common errors: One may be tempted to write the anionic part as dihyroxide and it is incorrect. The prefixes mono, di, tri, tetra etc are used only for binary covalent compounds. ...
... Common errors: One may be tempted to write the anionic part as dihyroxide and it is incorrect. The prefixes mono, di, tri, tetra etc are used only for binary covalent compounds. ...
RES8_chemcontentchecklist
... have different electronegativities, resulting in a polar bond. Describe intermolecular forces based on permanent dipoles, as in hydrogen chloride, and instantaneous dipoles (van der Waals’ forces), as in the noble gases. Describe hydrogen bonding, including the role of a lone pair, between molecules ...
... have different electronegativities, resulting in a polar bond. Describe intermolecular forces based on permanent dipoles, as in hydrogen chloride, and instantaneous dipoles (van der Waals’ forces), as in the noble gases. Describe hydrogen bonding, including the role of a lone pair, between molecules ...
Document
... of a solid at its melting point into Constant of a liquid at its boiling point into liquid is heat of fusion. temperature! vapor is heat of vaporization. Qfusion = (mass) (spec.heat of fusion) Qvaporization = (mass) (spec.heat of vaporization) Example 1: How many joules is needed to change 20.0 g of ...
... of a solid at its melting point into Constant of a liquid at its boiling point into liquid is heat of fusion. temperature! vapor is heat of vaporization. Qfusion = (mass) (spec.heat of fusion) Qvaporization = (mass) (spec.heat of vaporization) Example 1: How many joules is needed to change 20.0 g of ...
Example - Schoolwires.net
... Example: A hydrate of magnesium iodide has the formula MgI2 ∙ X H2O. To determine the value of X, a student heats a sample of the hydrate until all the water is gone. A 1.628 g sample of hydrate is heated to constant mass of 1.072 g. What is the value of X? ...
... Example: A hydrate of magnesium iodide has the formula MgI2 ∙ X H2O. To determine the value of X, a student heats a sample of the hydrate until all the water is gone. A 1.628 g sample of hydrate is heated to constant mass of 1.072 g. What is the value of X? ...
HCC9 Chapter 9 Objectives and Notes
... In a given chemical compound the elements are always combined in the same proportion by mass. a. H2O is always 2.02 g hydrogen for every 16.0 g oxygen, the ratio of the masses never varies. 2. law of multiple proportions: Discovered by John Dalton. When two elements combine to form a series of diffe ...
... In a given chemical compound the elements are always combined in the same proportion by mass. a. H2O is always 2.02 g hydrogen for every 16.0 g oxygen, the ratio of the masses never varies. 2. law of multiple proportions: Discovered by John Dalton. When two elements combine to form a series of diffe ...
Simple, accurate electrostatics-based formulas for calculating
... A set of simple analytic formulas is derived via electrostatics-based methods to accurately calculate the values of electron a⌅nities An and ionization potentials In for n-carbon icosahedral fullerene molecules as a function of their average radii Rn . These formulas reproduce with accuracy the valu ...
... A set of simple analytic formulas is derived via electrostatics-based methods to accurately calculate the values of electron a⌅nities An and ionization potentials In for n-carbon icosahedral fullerene molecules as a function of their average radii Rn . These formulas reproduce with accuracy the valu ...
... semiclassical techniques. The quantum calculations are relatively simple to perform for low-n states, but become increasingly difficult and less accurate as n increases. Semiclassical techniques are accurate and provide insight into the dynamics at high n, but become increasingly difficult to use an ...
Many-body properties of a spherical two
... multielectron bubbles form.2 These multielectron bubbles are spherical cavities in the helium liquid, containing from a few to several tens of millions of electrons. The bubble radius R is determined by balancing the Coulomb repulsion of the electrons in the bubble with the surface tension of the he ...
... multielectron bubbles form.2 These multielectron bubbles are spherical cavities in the helium liquid, containing from a few to several tens of millions of electrons. The bubble radius R is determined by balancing the Coulomb repulsion of the electrons in the bubble with the surface tension of the he ...
X-ray photoelectron spectroscopy
X-ray photoelectron spectroscopy (XPS) is a surface-sensitive quantitative spectroscopic technique that measures the elemental composition at the parts per thousand range, empirical formula, chemical state and electronic state of the elements that exist within a material. XPS spectra are obtained by irradiating a material with a beam of X-rays while simultaneously measuring the kinetic energy and number of electrons that escape from the top 0 to 10 nm of the material being analyzed. XPS requires high vacuum (P ~ 10−8 millibar) or ultra-high vacuum (UHV; P < 10−9 millibar) conditions, although a current area of development is ambient-pressure XPS, in which samples are analyzed at pressures of a few tens of millibar.XPS is a surface chemical analysis technique that can be used to analyze the surface chemistry of a material in its as-received state, or after some treatment, for example: fracturing, cutting or scraping in air or UHV to expose the bulk chemistry, ion beam etching to clean off some or all of the surface contamination (with mild ion etching) or to intentionally expose deeper layers of the sample (with more extensive ion etching) in depth-profiling XPS, exposure to heat to study the changes due to heating, exposure to reactive gases or solutions, exposure to ion beam implant, exposure to ultraviolet light.XPS is also known as ESCA (Electron Spectroscopy for Chemical Analysis), an abbreviation introduced by Kai Siegbahn's research group to emphasize the chemical (rather than merely elemental) information that the technique provides.In principle XPS detects all elements. In practice, using typical laboratory-scale X-ray sources, XPS detects all elements with an atomic number (Z) of 3 (lithium) and above. It cannot easily detect hydrogen (Z = 1) or helium (Z = 2).Detection limits for most of the elements (on a modern instrument) are in the parts per thousand range. Detection limits of parts per million (ppm) are possible, but require special conditions: concentration at top surface or very long collection time (overnight).XPS is routinely used to analyze inorganic compounds, metal alloys, semiconductors, polymers, elements, catalysts, glasses, ceramics, paints, papers, inks, woods, plant parts, make-up, teeth, bones, medical implants, bio-materials, viscous oils, glues, ion-modified materials and many others.XPS is less routinely used to analyze the hydrated forms of some of the above materials by freezing the samples in their hydrated state in an ultra pure environment, and allowing or causing multilayers of ice to sublime away prior to analysis. Such hydrated XPS analysis allows hydrated sample structures, which may be different from vacuum-dehydrated sample structures, to be studied in their more relevant as-used hydrated structure. Many bio-materials such as hydrogels are examples of such samples.