введение в общую introductio to the general ch ведение в общую
... the number of chemical bonds a given atom has formed in a given molecule. The number of bonds formed by a given element was originally thought to be a fixed chemical property. In fact, in most cases this is not true. For example, phosphorus often has a valence of three, but can also have other valen ...
... the number of chemical bonds a given atom has formed in a given molecule. The number of bonds formed by a given element was originally thought to be a fixed chemical property. In fact, in most cases this is not true. For example, phosphorus often has a valence of three, but can also have other valen ...
Deans Community High School Intermediate 2 Revision Notes www
... Uses of catalyst. As we have seen, reactions are more likely to take place when high concentrations, large surface areas and high temperatures are used. These factors increase the likelihood of collisions of the reactants, and the more energy that these collision have, the more likely it will be tha ...
... Uses of catalyst. As we have seen, reactions are more likely to take place when high concentrations, large surface areas and high temperatures are used. These factors increase the likelihood of collisions of the reactants, and the more energy that these collision have, the more likely it will be tha ...
1aUnit Two Handouts - Dunmore High School
... DECISION TREE: Should a formula be written as ions? Is the substance an acid (formula begins with H), a base (contains hydroxide ion), a salt (cation anion) or other? If it is an acid, go to A. If it is a base, go to B. If it is a salt, go to S. If it is an other, do not write it as ions. Example: Z ...
... DECISION TREE: Should a formula be written as ions? Is the substance an acid (formula begins with H), a base (contains hydroxide ion), a salt (cation anion) or other? If it is an acid, go to A. If it is a base, go to B. If it is a salt, go to S. If it is an other, do not write it as ions. Example: Z ...
sample chapter
... formula of acetic acid as CH3COOH we indicate that the ionizable proton is in the COOH group. The double arrow Δ in an equation means that the reaction is reversible; that is, the reaction can occur in both directions. Initially, a number of CH3COOH molecules break up to yield CH3COO⫺ and H⫹ ions. ...
... formula of acetic acid as CH3COOH we indicate that the ionizable proton is in the COOH group. The double arrow Δ in an equation means that the reaction is reversible; that is, the reaction can occur in both directions. Initially, a number of CH3COOH molecules break up to yield CH3COO⫺ and H⫹ ions. ...
1984 Advanced Placement Exam
... Note: For all questions referring to solutions, assume that the solvent is water unless otherwise stated. Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement and then blacken the corre ...
... Note: For all questions referring to solutions, assume that the solvent is water unless otherwise stated. Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement and then blacken the corre ...
2 - mrstorie
... 6. At 773 K, the reaction 2 NO (g) + O2 (g) 2 NO2 (g) produces the following concentrations: [NO] = 3.49 X 10-4M; [O2] = 0.80M; [NO2] = 0.25M. a. What is the equilibrium constant expression for this reaction? Kc = [NO]2/[NO]2[O2] b. What is the equilibrium constant for the reaction? 6.4 x 105 7. ...
... 6. At 773 K, the reaction 2 NO (g) + O2 (g) 2 NO2 (g) produces the following concentrations: [NO] = 3.49 X 10-4M; [O2] = 0.80M; [NO2] = 0.25M. a. What is the equilibrium constant expression for this reaction? Kc = [NO]2/[NO]2[O2] b. What is the equilibrium constant for the reaction? 6.4 x 105 7. ...
N5 Chemistry 2014
... A H2O(ℓ) + SO32—(aq) + Fe3+(aq) SO42—(aq) + 2H+(aq) + Fe2+(aq) + e— B H2O(ℓ) + SO32—(aq) + 2Fe3+(aq) SO42—(aq) + 2H+(aq) + 2Fe2+(aq) C SO42—(aq) + 2H+(aq) + Fe2+(aq) + e— H2O(ℓ) + SO32—(aq) + Fe3+(aq) D SO42—(aq) + 2H+(aq) + 2Fe2+(aq) H2O(ℓ) + SO32—(aq) + 2Fe3+(aq). 18. The apparatus below was set ...
... A H2O(ℓ) + SO32—(aq) + Fe3+(aq) SO42—(aq) + 2H+(aq) + Fe2+(aq) + e— B H2O(ℓ) + SO32—(aq) + 2Fe3+(aq) SO42—(aq) + 2H+(aq) + 2Fe2+(aq) C SO42—(aq) + 2H+(aq) + Fe2+(aq) + e— H2O(ℓ) + SO32—(aq) + Fe3+(aq) D SO42—(aq) + 2H+(aq) + 2Fe2+(aq) H2O(ℓ) + SO32—(aq) + 2Fe3+(aq). 18. The apparatus below was set ...
Section 4.9 Oxidation–Reduction Reactions
... Substances that dissolve in water to form solutions that can conduct electricity are called electrolytes Substances that dissolve in water to form solutions but cannot conduct electricity are called nonelectrolytes ...
... Substances that dissolve in water to form solutions that can conduct electricity are called electrolytes Substances that dissolve in water to form solutions but cannot conduct electricity are called nonelectrolytes ...
A flask contains 0
... REMEMBER every time you turn the page…make sure that you have bubbled the correct number on the answer. This way if you get off track on bubbling, you only have to check a page to find your mistake. The AP-style multiple-choice questions will be of four types: Which of the following is set up co ...
... REMEMBER every time you turn the page…make sure that you have bubbled the correct number on the answer. This way if you get off track on bubbling, you only have to check a page to find your mistake. The AP-style multiple-choice questions will be of four types: Which of the following is set up co ...
Chapter 4 Aqueous Reactions and Solution Stoichiometry
... All salts containing the anions: CO32-, PO43-, AsO43-, S2- and SO32- are insoluble except fro IA metals and NH4+ salts. For salts containing the anions not mentioned above (e.g., CrO42-, Cr2O72-Aqueous , P3-, C2O42- etc.) assume that they are insoluble except for IA metals and NH4+ Reactions salts, ...
... All salts containing the anions: CO32-, PO43-, AsO43-, S2- and SO32- are insoluble except fro IA metals and NH4+ salts. For salts containing the anions not mentioned above (e.g., CrO42-, Cr2O72-Aqueous , P3-, C2O42- etc.) assume that they are insoluble except for IA metals and NH4+ Reactions salts, ...
KS4-Rates - Free Exam Papers
... 1. Energy is needed to break the bonds in petrol before new bonds can be formed by a reaction with oxygen. 2. Once some of the bonds in one petrol molecule have been broken the subsequent reaction with oxygen gives out enough energy to break the bonds in several other petrol molecules - and so on. ...
... 1. Energy is needed to break the bonds in petrol before new bonds can be formed by a reaction with oxygen. 2. Once some of the bonds in one petrol molecule have been broken the subsequent reaction with oxygen gives out enough energy to break the bonds in several other petrol molecules - and so on. ...
coordination compounds - Ahlcon Public School , Mayur Vihar Ph
... 37. When a mixture of NH 4Cl and K 2 Cr2 O7 are heated, stable colourless gas (A) was evolved which did not support combustion but magnesium continued to burn in it. The gas (A) reacted with calcium carbide in an electric furnanance forming a solid (B). The compound (B) was slowly hydrolysed by wate ...
... 37. When a mixture of NH 4Cl and K 2 Cr2 O7 are heated, stable colourless gas (A) was evolved which did not support combustion but magnesium continued to burn in it. The gas (A) reacted with calcium carbide in an electric furnanance forming a solid (B). The compound (B) was slowly hydrolysed by wate ...
Water - UFMG
... are a consequence of attractions between adjacent water molecules that give liquid water great internal cohesion. A look at the electron structure of the H2O molecule reveals the cause of these intermolecular attractions. Each hydrogen atom of a water molecule shares an electron pair with the oxygen ...
... are a consequence of attractions between adjacent water molecules that give liquid water great internal cohesion. A look at the electron structure of the H2O molecule reveals the cause of these intermolecular attractions. Each hydrogen atom of a water molecule shares an electron pair with the oxygen ...
Acid
An acid (from the Latin acidus/acēre meaning sour) is a chemical substance whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals (like calcium) to form salts. Aqueous solutions of acids have a pH of less than 7. Non-aqueous acids are usually formed when an anion (negative ion) reacts with one or more positively charged hydrogen cations. A lower pH means a higher acidity, and thus a higher concentration of positive hydrogen ions in the solution. Chemicals or substances having the property of an acid are said to be acidic.There are three common definitions for acids: the Arrhenius definition, the Brønsted-Lowry definition, and the Lewis definition. The Arrhenius definition defines acids as substances which increase the concentration of hydrogen ions (H+), or more accurately, hydronium ions (H3O+), when dissolved in water. The Brønsted-Lowry definition is an expansion: an acid is a substance which can act as a proton donor. By this definition, any compound which can easily be deprotonated can be considered an acid. Examples include alcohols and amines which contain O-H or N-H fragments. A Lewis acid is a substance that can accept a pair of electrons to form a covalent bond. Examples of Lewis acids include all metal cations, and electron-deficient molecules such as boron trifluoride and aluminium trichloride.Common examples of acids include hydrochloric acid (a solution of hydrogen chloride which is found in gastric acid in the stomach and activates digestive enzymes), acetic acid (vinegar is a dilute solution of this liquid), sulfuric acid (used in car batteries), and tartaric acid (a solid used in baking). As these examples show, acids can be solutions or pure substances, and can be derived from solids, liquids, or gases. Strong acids and some concentrated weak acids are corrosive, but there are exceptions such as carboranes and boric acid.