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chemical reactions
chemical reactions

... 1. A balanced chemical reaction- both sides of equation have the same number of atoms of each element ...
Oxidation-Reduction Reactions Oxidation-Reduction
Oxidation-Reduction Reactions Oxidation-Reduction

... Fluorine is 1 in all of its compounds. The other halogens are 1 unless the other element is another halogen or oxygen. ...
Notes
Notes

... 2. Electron gain and loss 3. Agents Electrochemistry is the study of the interchange of chemical and electrical energy.  Reactions with electron transfers are commonly called oxidation-reduction reactions (redox reactions)  Not all reactions involve an electron transfer – these reactions are refer ...
File - LSAmockscience
File - LSAmockscience

... • When one element replaces another element in a compound A + BC  AC + B Element + compound  new element + new compound ...
Packet
Packet

... 32. A change in the force of Earth’s gravity on an object will affect its a. mass b. density c. weight d. kinetic energy 33. Chemical proprieties a. include changes of state of a substance b. include mass and color c. include changes that alter the identity of a substance d. can be observed without ...
Qualitative Analysis Lab
Qualitative Analysis Lab

... Chemical reactions can be grouped into different classes, such as precipitation reactions, acidbase (or neutralization) reactions, gas-formation reactions, and oxidation-reduction (or redox) reactions. There are several other classifications, too, such as combination reactions, decomposition reactio ...
hc1(8)notes
hc1(8)notes

... • To complete the process of writing a correct equation, the law of conservation of mass must be taken into account. • The relative amounts of reactants and products represented in the equation must be adjusted so that the numbers and types of atoms are the same on both sides of the equation. • This ...
PDF
PDF

... COMBINATION REACTIONS • In combination reactions two or more substances react to form a single substance. Combination reactions may be either redox or nonredox reactions. • The general form of the equation for a combination reaction is: A + B C • An example of a redox combination reaction is: S(s) + ...
PPT
PPT

... • In decomposition reactions one substance is broken down into two or more simpler substances. Decomposition reactions may be either redox or nonredox reactions. • The general form of the equation for a decomposition reaction is: A B + C. • An example of a redox decomposition reaction is: 2HI(g) H2 ...
Honors Midterm - Stamford High School
Honors Midterm - Stamford High School

... 3. Make an element inventory. How are you going to know if the equation is balanced if you don't actually make a list of how many of each atom you have? You won't. You have to make an inventory of how many atoms of each element you have, and then you have to keep it current throughout the whole prob ...
Acids and Bases - Personal.kent.edu
Acids and Bases - Personal.kent.edu

... H+ + H2 O F G H3 O+ Common strong acids include: H3 O+ , H2 SO4 , HNO3 , HCl, HBr, and HI Base According to the Brφnsted-Lowry definition, a base is a proton (H + ) acceptor. Conjugate Pairs In a chemical reaction, the product obtained from and acid-base reaction of an acid is a molecule with one fe ...
+ H 2 O(l)
+ H 2 O(l)

... • List of metals in order of decreasing ease of oxidation. • Alkali and alkaline earth metals are at the top. (active metals) • Gold, Silver, Platinum, and palladium are considered to be (noble metals) because they resist oxidation. ...
CHEMISTRY
CHEMISTRY

A-level Paper 3 Practice Paper 3 - A
A-level Paper 3 Practice Paper 3 - A

groups (families) vs rows
groups (families) vs rows

UNIT 1 - StudyGuide.PK
UNIT 1 - StudyGuide.PK

... Show understanding, including reference to the Boltzmann distribution, of what is meant by the term activation energy ...
system = part of the universe that contains the reaction or process
system = part of the universe that contains the reaction or process

... Mass of water = 75g Initial Temperature of water = 21.0ºC Final Temperature of water = 25.5ºC ...
File
File

... Nitrogen dioxide + water(l)  nitric acid + nitrogen monoxide Nitrogen dioxide(g) + water(l)  nitric acid(aq) + nitrogen monoxide(g) NO2(g) + H2O(l)  HNO3(aq) + NO(g) 3 NO2(g) + H2O(l)  2 HNO3(aq) + NO(g) ...
physics - Keith E. Holbert
physics - Keith E. Holbert

... = Z M H −1 + N m n − M X where mX is the mass of the nucleus, MX is the mass of the neutral atom, and MH-1 is the mass of the neutral hydrogen atom, 1H. The latter expression given in Equation (1) is the most convenient since the mass of the nucleus is rarely tabulated but the mass of the neutral at ...
Practice Questions
Practice Questions

... Calculate the number of moles of sodium bicarbonate that were added to the respective flasks. (The moles of hydrochloric acid in all 3 flasks is equal to its molarity (1.0 mol / L) x 70.0 ml x 1.00 L / 1,000. mL) Calculate the number of moles of CO2 theoretically produced and then calculate the resp ...
Thermodynamics and kinetics
Thermodynamics and kinetics

...  below ≈1E-5/mL no visible precipitate forms colloids • formation of supersaturated solutions  slow kinetics • Competitive reactions may lower free ion concentration • Large excess of ligand may form soluble species  AgCl(s) + Cl- <--> AgCl2-(aq) Ksp really best for slightly soluble salts ...
Document
Document

Review Material
Review Material

... is 2+ (e.g. Ti2+ & Fe2+). When such ions are formed, the transition metal atom loses its two 4s electrons (3d electrons are not lost). (In fact, whenever a positive ion is formed from an atom, electrons are always lost first from the subshell having the largest value of n). Thus, in forming ions, tr ...
AP Chem Stoichiometry Topic#4 Questions WS Name: Date: Per
AP Chem Stoichiometry Topic#4 Questions WS Name: Date: Per

... (4) Based on the structural formula, calculate the percentage of carbon by mass present in the compound. (5) The diagram represents the collection of elements formed by a decomposition reaction. (a) If the blue spheres represent N atoms and the red ones represent O atoms, what was the empirical form ...
Chemical equilibrium, redox and pE
Chemical equilibrium, redox and pE

... •  Thermodynamics applied to redox speciation •  Redox speciation has profound effects on chemical and biological processes •  Photosynthetic organisms, altered Earth’s redox conditions from reducing to oxidising •  Profound consequences for life •  Anoxic conditions exist today ...
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Lewis acid catalysis



In Lewis acid catalysis of organic reactions, a metal-based Lewis acid acts as an electron pair acceptor to increase the reactivity of a substrate. Common Lewis acid catalysts are based on main group metals such as aluminum, boron, silicon, and tin, as well as many early (titanium, zirconium) and late (iron, copper, zinc) d-block metals. The metal atom forms an adduct with a lone-pair bearing electronegative atom in the substrate, such as oxygen (both sp2 or sp3), nitrogen, sulfur, and halogens. The complexation has partial charge-transfer character and makes the lone-pair donor effectively more electronegative, activating the substrate toward nucleophilic attack, heterolytic bond cleavage, or cycloaddition with 1,3-dienes and 1,3-dipoles.Many classical reactions involving carbon–carbon or carbon–heteroatom bond formation can be catalyzed by Lewis acids. Examples include the Friedel-Crafts reaction, the aldol reaction, and various pericyclic processes that proceed slowly at room temperature, such as the Diels-Alder reaction and the ene reaction. In addition to accelerating the reactions, Lewis acid catalysts are able to impose regioselectivity and stereoselectivity in many cases.Early developments in Lewis acid reagents focused on easily available compounds such as TiCl4, BF3, SnCl4, and AlCl3. The relative strengths of these (and other) Lewis acids may be estimated from NMR spectroscopy by the Childs method or the Gutmann-Beckett method. Over the years, versatile catalysts bearing ligands designed for specific applications have facilitated improvement in both reactivity and selectivity of Lewis acid-catalyzed reactions. More recently, Lewis acid catalysts with chiral ligands have become an important class of tools for asymmetric catalysis.Challenges in the development of Lewis acid catalysis include inefficient catalyst turnover (caused by catalyst affinity for the product) and the frequent requirement of two-point binding for stereoselectivity, which often necessitates the use of auxiliary groups.
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