This energy is sufficient to excite the electron to higher energy level.Therefore spectroscopy in this region is also called as 'electronic spectroscopy'. A molecule can have electrons in sigma bonding orbitals, pi bonding orbitals or non bonding orbitals.As a molecule containing pi bonding electrons or non bonding electrons absorbs a UV radiation it excites the electrons to higher anti-bonding orbitals.So the following electronic transitions are
Moran 2 An element in chemistry is more than just an element; at least Chlorine is more than just an element. It is very useful in many ways that help people today. Chlorine is a common nonmetallic element belonging to the halogens; it is a heavy yellow irritating toxic gas; it is used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt. People should know more about the uses of chlorine and why chlorine is used in many processes, for example; bleaching, and why we use it today. Everything has to start somewhere, and chlorine was produced many years ago.
Hydrogen gas was first identified as an element in 1766, by British scientist Henry Cavendish, in an experiment wherein he separated hydrogen gas by reacting zinc metal plates with hydrochloric acid. Cavendish found that when he applied a spark to the resulting hydrogen gas, it yielded water. It wasn’t until some years later that French chemist Antoine Lavoisier gave hydrogen its modern name. The word hydrogen is derived from the Greek words ‘hydro’ and ‘genes’, which translate as ‘born of water.’ In 1800, two English scientists, William Nicholson and Sir Anthony Carlisle, discovered electrolysis. They found that by applying an electric current to water, the resulting reaction produced both oxygen and hydrogen gases.
Oxyhydrogen gas which was produced by electrolysis is then injected into vehicle 's air intake system as a supplemental fuel. Oxyhydrogen gas has proven to increase mileage, improving power and lowering emissions. Providing Oxyhydrogen is better than providing pure Hydrogen since Oxygen is mandatory for combustion which is present in Oxyhydrogen. Adding Oxyhydrogen causes gasoline or diesel to ignite faster and more efficiently, resulting in higher FUEL ECONOMY and dramatically LOWER EMISSIONS. Over 60% of the gasoline is wasted through fumes, vibration, evaporation and unburned fuel.
‘Its use being to help in the desensitization of sore teeth, and it is commonly used in many toothpaste products.’ (PNA) Sodium nitrate known as NaNO3 is a combination of sodium and nitrogen and is found in a powder like form. This substance is used every day in the use of pesticides and helps in getting rid of insects and pest that could be a threat to important crops.
He chose the name chromium from the Greek word chroma, which means color. Chromium was a good choice of name, many chromium compounds are brightly colored. Rubies are red and emeralds are green because they contain chromium compounds. Some of the brightest colors in the artist's palette contain chromium. Chrome yellow is made from a substance which contains chromium, lead, and oxygen.
Radioactivity Introduction: During this report explanations of the constituents and structure of atoms will be discussed. The basic and quantum models of an atom will be discussed and compared. Three different types of radiation will be looked which include alpha, beta and gamma. The nature and emission of these types of radiation will be reported as well as the penetrable force. The range and effects the radiation have on the magnetic and electrical fields.
The electrons form orbitals around the nucleus and cause most of the chemical properties of that element. When an atom's outermost orbital gains or loses electrons (also known as valence electrons), the atom forms an ion. Ionic bonds are formed when attractions between oppositely charged atoms or groups of atoms of electrons are donated and accepted. Electrons transfer between Na and Cl. Valence electrons are important roles in many atoms, ionic bonds, covalent bonds etc... Valence electrons are the electrons of an atom that can participate in the formation of chemical bonds with other atoms.
PL canoccur in gas, liquid and solid phases. An energy level diagram as in Figure 1.1 can illustrate the radiative and non-radiativetransitions that lead to the observation of molecular photoluminescence. The spin multiplicities of a given electronic state can either a singlet @aired electrons) or a triplet (unpaired electrons). The ground electronic state is normally a singlet state and is designated as SO. Excited electronic states are either singlet (SI.
From the primary beam (generated by the electron gun) some electrons are get reflected or bounced back by the sampl... ... middle of paper ... ...hich describes the angle at which a beam of X-rays of a particular wavelength diffracts from a crystalline surface. Bragg’s Law is as follows: ƛ=2d sinθ Where: θ = Bragg angle; ƛ = is the incident wavelength; d= is the spacing between different planes. We can measure the Bragg angle (2θ). This is the position of the Bragg reflection, or peak. Then, since we know the wavelength (ƛ), of the X-rays, we can then calculate the d-spacing (the distance between different planes in the crystal) from Bragg’s Law (Equation 3-36) A typical X-ray diffraction pattern is in the form of a graph, with a series of peaks (the actual diffraction pattern), with the horizontal axis being 2θ, or twice the Bragg angle; and the vertical axis is the intensity, or the X-ray count measured by the detector, which is a function of the crystal structure and the orientation of the crystallites.