Calculations and the Chemical Equation
... 7. Give the symbol(s) needed to show the smallest unit of nitrogen as it is normally found in nature. 8. When a solid compound is described as a "hydrate", what does this mean? 9. What is the difference in meaning between "2O" and "O2" when they occur in chemical equations? 10. 6.022 ´ 1023 molecule ...
... 7. Give the symbol(s) needed to show the smallest unit of nitrogen as it is normally found in nature. 8. When a solid compound is described as a "hydrate", what does this mean? 9. What is the difference in meaning between "2O" and "O2" when they occur in chemical equations? 10. 6.022 ´ 1023 molecule ...
Molecular Perspective of Static Wetting: Simulation and
... wetting properties of a monolayer of graphene is developed, which experimentally were unknown. While in the literature for the contact angle of water on graphite values in the range of 90−95° have been reported, it has been suggested that the contact angle on graphene may either be as high as 127° o ...
... wetting properties of a monolayer of graphene is developed, which experimentally were unknown. While in the literature for the contact angle of water on graphite values in the range of 90−95° have been reported, it has been suggested that the contact angle on graphene may either be as high as 127° o ...
Phase behavior of clathrate hydrates: a model for single and
... empty hydrate lattice molar volume, V w (T; P), can be found in Klauda and Sandler (2000). As previously stated, the crystal lattice size (or alternatively the molar volume) depends on the guest. There are limited data on the temperature dependence of the molar volume; therefore, we assume that it ...
... empty hydrate lattice molar volume, V w (T; P), can be found in Klauda and Sandler (2000). As previously stated, the crystal lattice size (or alternatively the molar volume) depends on the guest. There are limited data on the temperature dependence of the molar volume; therefore, we assume that it ...
Heterogeneous Catalysis and Solid Catalysts
... The term green catalytic processes has been used frequently in recent years, implying that chemical processes may be made environmentally benign by taking advantage of the possible high yields and selectivities for the target products, with little or no unwanted side products and also often high ene ...
... The term green catalytic processes has been used frequently in recent years, implying that chemical processes may be made environmentally benign by taking advantage of the possible high yields and selectivities for the target products, with little or no unwanted side products and also often high ene ...
Noncovalent interactions of molecules with single walled carbon
... to the exterior of a carbon nanotube would change hybridisation of C-atom to sp3 and would partly relieve strain energy.25,26 However, addition of an atom to the interior of the sidewall would add strain energy to the nanotube. Theoretical modelling has shown that the interior of a SWNT is more iner ...
... to the exterior of a carbon nanotube would change hybridisation of C-atom to sp3 and would partly relieve strain energy.25,26 However, addition of an atom to the interior of the sidewall would add strain energy to the nanotube. Theoretical modelling has shown that the interior of a SWNT is more iner ...
The Integument of Water-walking Arthropods: Form and Function John W.M. Bush
... of increasing surface tension. This means of propulsion, termed Marangoni propulsion (Bush and Hu, 2006), is used as an escape mechanism by a number of water-walking insects, as well as beetles and terrestrial insects that accidentally fall onto the water surface (Fig. 2b). By releasing a lipid that ...
... of increasing surface tension. This means of propulsion, termed Marangoni propulsion (Bush and Hu, 2006), is used as an escape mechanism by a number of water-walking insects, as well as beetles and terrestrial insects that accidentally fall onto the water surface (Fig. 2b). By releasing a lipid that ...
Organic Reactions in Organised Media
... reactant prefers a nonpolar phase. There are several methods to overcome the incompatibility between reactants. One of them is to use an aprotic polar solvent like dimethylsulfoxide, dimethylformamide, acetonitrile, or hexamethylphosphorotriamide, which is favourable for SN2 reactions, or a protic p ...
... reactant prefers a nonpolar phase. There are several methods to overcome the incompatibility between reactants. One of them is to use an aprotic polar solvent like dimethylsulfoxide, dimethylformamide, acetonitrile, or hexamethylphosphorotriamide, which is favourable for SN2 reactions, or a protic p ...
Molecular Dynamics Simulation of the
... data for the different salts. The numbers provided above can be absolute quantitative indicators only if they stem from a large number of NVT MD simulations for each system, which is hardly plausible at the current state of computational power. Nevertheless, they reflect appropriately the aggregation ...
... data for the different salts. The numbers provided above can be absolute quantitative indicators only if they stem from a large number of NVT MD simulations for each system, which is hardly plausible at the current state of computational power. Nevertheless, they reflect appropriately the aggregation ...
book problems c 10.
... atomic mass, and the unit cell length, determined from x-ray methods. To be useful for this purpose, the crystal must be free of defects. Very accurate values of these quantities for silicon have been measured at the National Institute for Standards and Technology (NIST). To use this approach, it is ...
... atomic mass, and the unit cell length, determined from x-ray methods. To be useful for this purpose, the crystal must be free of defects. Very accurate values of these quantities for silicon have been measured at the National Institute for Standards and Technology (NIST). To use this approach, it is ...
The Project Gutenberg eBook #50880: Treatise on Thermodynamics.
... on touching a body. This direct sensation, however, furnishes no quantitative scientific measure of a body’s state with regard to heat; it yields only qualitative results, which vary according to external circumstances. For quantitative purposes we utilize the change of volume which takes place in a ...
... on touching a body. This direct sensation, however, furnishes no quantitative scientific measure of a body’s state with regard to heat; it yields only qualitative results, which vary according to external circumstances. For quantitative purposes we utilize the change of volume which takes place in a ...
Adsorption and Reaction of SO2 with a Polycrystalline UO2 Film
... All experiments were carried out under UHV conditions in a chamber with base pressure of ∼5 × 10-11 Torr. The chamber is equipped with XPS, TPD, and LEIS. A detailed description of the experimental apparatus has been given previously.12,13 The sample is mounted onto an x-y-z rotary manipulator, whic ...
... All experiments were carried out under UHV conditions in a chamber with base pressure of ∼5 × 10-11 Torr. The chamber is equipped with XPS, TPD, and LEIS. A detailed description of the experimental apparatus has been given previously.12,13 The sample is mounted onto an x-y-z rotary manipulator, whic ...
Role of Pt-precursor on the performance of Pt/BaCO3/Al2O3·NOx
... with alumina, impregnated with Ba(NO3 )2 and, finally, impregnated with platinum. Four different platinum precursors were used in the preparation (one for each sample). The preparation method is described in detail in [26]. Briefly, the monoliths were coated with alumina by immersing the monolith in ...
... with alumina, impregnated with Ba(NO3 )2 and, finally, impregnated with platinum. Four different platinum precursors were used in the preparation (one for each sample). The preparation method is described in detail in [26]. Briefly, the monoliths were coated with alumina by immersing the monolith in ...
Sustainable Oxidation Catalysis for Synthesis
... oxidize almost any organic molecule, yielding CO2 and inorganic ions. The versatility of the AOPs is enhanced by the fact that there are different ways of producing hydroxyl radicals, facilitating compliance with the specific treatment requirements. Several promising cost-cutting approaches have bee ...
... oxidize almost any organic molecule, yielding CO2 and inorganic ions. The versatility of the AOPs is enhanced by the fact that there are different ways of producing hydroxyl radicals, facilitating compliance with the specific treatment requirements. Several promising cost-cutting approaches have bee ...
Effect of Long Chain Alcohols on Micellar Relaxation Time and
... The effect of long chain alcohols (5 mol% CnOH for n 5 8, 10, 12, 14, and 16) on the micellar stability of sodium dodecyl sulfate (SDS) solutions (SDS concentration ranging from 25 to 200 mM) was investigated and related to foaming properties, such as foamability, dynamic and equilibrium surface ten ...
... The effect of long chain alcohols (5 mol% CnOH for n 5 8, 10, 12, 14, and 16) on the micellar stability of sodium dodecyl sulfate (SDS) solutions (SDS concentration ranging from 25 to 200 mM) was investigated and related to foaming properties, such as foamability, dynamic and equilibrium surface ten ...
Unit 3 2 Basic Mole Conversions and Mole Maps
... Meaning: For every 2 mol of ethane, 7 mol of dioxygen molecules are consumed in the combustion (a ratio of 2 to 7) This produces 4 moles of carbon dioxide, 6 moles of water and releases 3,170 kJ of energy from the bonding chemicals to the environment. This set of relationships can indicate, at a gla ...
... Meaning: For every 2 mol of ethane, 7 mol of dioxygen molecules are consumed in the combustion (a ratio of 2 to 7) This produces 4 moles of carbon dioxide, 6 moles of water and releases 3,170 kJ of energy from the bonding chemicals to the environment. This set of relationships can indicate, at a gla ...
chemistry worksheet # 2: the mole as a unit of mass
... complete work each day as it is assigned, this will not be a difficult unit. That is good, because stoichiometry is one of the most central and important concepts in chemistry. It is essential that you understand this unit in order to move forward in chemistry. In short: do not fall behind or you wi ...
... complete work each day as it is assigned, this will not be a difficult unit. That is good, because stoichiometry is one of the most central and important concepts in chemistry. It is essential that you understand this unit in order to move forward in chemistry. In short: do not fall behind or you wi ...
The Chemistry and Applications of Metal
... a cubic framework (Fig. 2, figs. S2 and S3, and tables S1 and S2). The architectural robustness of MOF-5 allowed for gas sorption measurements, which revealed 61% porosity and a BrunauerEmmett-Teller (BET) surface area of 2320 m2/g (2900 m2/g Langmuir). These values are substantially higher than tho ...
... a cubic framework (Fig. 2, figs. S2 and S3, and tables S1 and S2). The architectural robustness of MOF-5 allowed for gas sorption measurements, which revealed 61% porosity and a BrunauerEmmett-Teller (BET) surface area of 2320 m2/g (2900 m2/g Langmuir). These values are substantially higher than tho ...
Adsorption
Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. This process differs from absorption, in which a fluid (the absorbate) permeates or is dissolved by a liquid or solid (the absorbent). Adsorption is a surface-based process while absorption involves the whole volume of the material. The term sorption encompasses both processes, while desorption is the reverse of it. Adsorption is a surface phenomenon.Similar to surface tension, adsorption is a consequence of surface energy. In a bulk material, all the bonding requirements (be they ionic, covalent, or metallic) of the constituent atoms of the material are filled by other atoms in the material. However, atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms and therefore can attract adsorbates. The exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as physisorption (characteristic of weak van der Waals forces) or chemisorption (characteristic of covalent bonding). It may also occur due to electrostatic attraction.Adsorption is present in many natural, physical, biological, and chemical systems, and is widely used in industrial applications such as activated charcoal, capturing and using waste heat to provide cold water for air conditioning and other process requirements (adsorption chillers), synthetic resins, increase storage capacity of carbide-derived carbons, and water purification. Adsorption, ion exchange, and chromatography are sorption processes in which certain adsorbates are selectively transferred from the fluid phase to the surface of insoluble, rigid particles suspended in a vessel or packed in a column. Pharmaceutical industry applications, which use adsorption as a means to prolong neurological exposure to specific drugs or parts thereof, are lesser known.However, it should be remarked that the distinction between adsorption and absorption vanishes as we go from perfectly crystalline macroscopic materials to porous/structured materials, aggregates and composites made out of increasingly smaller grains, viz., micron-sized particles to nanoparticles, sub-nano particles and finally molecules (or atoms). In such nano-composites, the internal surface area of particulate matter is very large. Then the adsorption on internal surfaces simply becomes absorption when viewed from the bulk. Then the distinction between adsorption and absorption vanishes. On the other hand, the distinction is clearest between bulk solids without internal structure, but having only surfaces where only adsorption can occur on the outer surfaces, and nanocomposites or aggregates with internal structure where absorption by the host material is simply adsorption on internal surfaces of the host material. As an example, we may consider a crystalline piece of silicon dioxide (quartz) which can adsorb water molecules on its surface. However, if the quartz is ground into very fine sand, the pile of sand (an aggregate) has a very large internal surface area. A very large amount of water can be adsorbed by the ""internal"" surfaces of the grains in the pile of sand, and this absorption is simply ""internal adsorption. If water is made to flow thorugh such a pile of sand, ions and toxins in the water may be preferentially adsorbed by the surfaces of the grains of sand, providing a simple, well-known water purification application.The word ""adsorption"" was coined in 1881 by German physicist Heinrich Kayser (1853-1940).