caribbeanexaminations council report on candidates` work in
... Part (a) (i) of the question was generally well answered with most candidates scoring full marks for correctly reading the burette. A few candidates, however, incorrectly read the burette scale “bottom up “ rather than “top down” For example, a correct burette reading of “1.3” was given as “2.7”. Al ...
... Part (a) (i) of the question was generally well answered with most candidates scoring full marks for correctly reading the burette. A few candidates, however, incorrectly read the burette scale “bottom up “ rather than “top down” For example, a correct burette reading of “1.3” was given as “2.7”. Al ...
TOPIC 11 Further equilibrium 11.1 Chemical equilibrium
... If the amount of H2(g) at equilibrium has increased, then the position of equilibrium has shifted to the left. Since this shift has been caused by an increase in temperature, the reverse reaction must be endothermic. Hence the forward reaction must be exothermic. ...
... If the amount of H2(g) at equilibrium has increased, then the position of equilibrium has shifted to the left. Since this shift has been caused by an increase in temperature, the reverse reaction must be endothermic. Hence the forward reaction must be exothermic. ...
Photogeneration of Hydride Donors and Their Use Toward CO2
... difficult to convert to the formyl anion by hydride transfer reactions, however, M−CO is much easier to ΔH‡ = −0.6 kcal/mol convert to M−CHO. Our calculations also show that ΔG‡ = 12.6 kcal/mol the further photoreduction of [1•HH]2+ can create a [1•HH]•+ species with a dramatically increased hydrici ...
... difficult to convert to the formyl anion by hydride transfer reactions, however, M−CO is much easier to ΔH‡ = −0.6 kcal/mol convert to M−CHO. Our calculations also show that ΔG‡ = 12.6 kcal/mol the further photoreduction of [1•HH]2+ can create a [1•HH]•+ species with a dramatically increased hydrici ...
chemistry sp.indd
... This booklet of specimen materials is for use from 2008. It is intended for use with the version of the syllabus that will be examined in 2010, 2011 and 2012. The purpose of these materials is to provide Centres with a reasonable idea of the general shape and character of the planned question papers ...
... This booklet of specimen materials is for use from 2008. It is intended for use with the version of the syllabus that will be examined in 2010, 2011 and 2012. The purpose of these materials is to provide Centres with a reasonable idea of the general shape and character of the planned question papers ...
Final Exam - KFUPM Faculty List
... this has a [Ne]3s1 configuration, thus the big jump would occur at I2, thus it cannot be Na C) Al this has a [Ne]3s23p1 configuration, thus the big jump would occur at I4, thus it cannot be Al D) Si this has a [Ne]3s23p2 configuration, thus the big jump would occur at I5, thus it cannot be Si E) P t ...
... this has a [Ne]3s1 configuration, thus the big jump would occur at I2, thus it cannot be Na C) Al this has a [Ne]3s23p1 configuration, thus the big jump would occur at I4, thus it cannot be Al D) Si this has a [Ne]3s23p2 configuration, thus the big jump would occur at I5, thus it cannot be Si E) P t ...
Chapter 14 (Kinetics) – Slides and Practice
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
Surface and sub-surface reactions during low temperature
... (Ultramid(R) B27 02, BASF Mn z 16 kDa) in formic acid (Fluka Analytical, 98% purity, 2% H2O). Approximately 80 ml of the solution were then dispensed onto a silicon or quartz substrate and spuncast at 6000 rpm for 1 min, also resulting in a film 30 nm thick. Atomic layer deposition reactor and pro ...
... (Ultramid(R) B27 02, BASF Mn z 16 kDa) in formic acid (Fluka Analytical, 98% purity, 2% H2O). Approximately 80 ml of the solution were then dispensed onto a silicon or quartz substrate and spuncast at 6000 rpm for 1 min, also resulting in a film 30 nm thick. Atomic layer deposition reactor and pro ...
Chapter
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
Rubidium
... Some potassium minerals and potassium chlorides also contain the element in commercially significant amounts. One notable source is also in the extensive deposits of pollucite at Bernic Lake, Manitoba. Rubidium metal can be produced by reducing rubidium chloride with calcium among other methods. ...
... Some potassium minerals and potassium chlorides also contain the element in commercially significant amounts. One notable source is also in the extensive deposits of pollucite at Bernic Lake, Manitoba. Rubidium metal can be produced by reducing rubidium chloride with calcium among other methods. ...
Document
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
... The sum of the exponents on the reactants is called the order of the reaction The rate law for the reaction 2 NO(g) + O2(g) 2 NO2(g) is Rate = k[NO]2[O2] The reaction is ...
Chemistry II - Mr. Dougan`s Wonderful World of Chemistry
... as ions, while water is a weak electrolyte and must be written in molecular form. Since the sodium and chloride ions do not change their form in this reaction, you will be determining the heat of formation for water. The heat evolved in these reactions is essentially a measure of the greater thermod ...
... as ions, while water is a weak electrolyte and must be written in molecular form. Since the sodium and chloride ions do not change their form in this reaction, you will be determining the heat of formation for water. The heat evolved in these reactions is essentially a measure of the greater thermod ...
Ch 12 Solutions
... into ions, which is a chemical process. - Sodium and chloride ions are the solutes in this aqueous solution, and water is the solvent. - Sodium chloride is not the actual solute, because it has dissociated and is not truly present. - Dissolving a completely covalent compound does not involve dissoci ...
... into ions, which is a chemical process. - Sodium and chloride ions are the solutes in this aqueous solution, and water is the solvent. - Sodium chloride is not the actual solute, because it has dissociated and is not truly present. - Dissolving a completely covalent compound does not involve dissoci ...
Grossmont College Chemistry 141 Laboratory Manual 6th Edition
... as the uncertainty in the measurement using statistical quantities. There are two types of errors, systematic errors and random errors. Random errors are the uncertainties associated with a measuring device; for example, an object measured for length may fall between the smallest divisions on a rule ...
... as the uncertainty in the measurement using statistical quantities. There are two types of errors, systematic errors and random errors. Random errors are the uncertainties associated with a measuring device; for example, an object measured for length may fall between the smallest divisions on a rule ...
Energy Changes in Chemical Reactions
... This reaction is an endothermic process because heat has to be supplied to the system (i.e., to HgO) by the surroundings [Figure 10.2(b)] in order for the reaction to occur. Thus, thermal energy is transferred from the surroundings to the system in an endothermic process. According to Figure 10.2, t ...
... This reaction is an endothermic process because heat has to be supplied to the system (i.e., to HgO) by the surroundings [Figure 10.2(b)] in order for the reaction to occur. Thus, thermal energy is transferred from the surroundings to the system in an endothermic process. According to Figure 10.2, t ...
Chapter 9 - HCC Learning Web
... 80. Use bond energies to estimate the enthalpy change for the reaction of one mole of CH4 with chlorine gas to give CH3Cl and hydrogen chloride. BE(C-H) = 414 kJ/mol BE(C-Cl) = 326 kJ/mol BE(H-Cl) = 432 kJ/mol BE(Cl-Cl) = 243 kJ/mol A. B. C. D. E. ...
... 80. Use bond energies to estimate the enthalpy change for the reaction of one mole of CH4 with chlorine gas to give CH3Cl and hydrogen chloride. BE(C-H) = 414 kJ/mol BE(C-Cl) = 326 kJ/mol BE(H-Cl) = 432 kJ/mol BE(Cl-Cl) = 243 kJ/mol A. B. C. D. E. ...
AQA A-level Chemistry
... l If two moles of a fuel are combusted then the standard enthalpy of reaction is the standard enthalpy of combustion multiplied by 2. l If four moles of a compound are formed from its elements in their standard states, then the standard enthalpy of formation value must be multiplied by 4 to get th ...
... l If two moles of a fuel are combusted then the standard enthalpy of reaction is the standard enthalpy of combustion multiplied by 2. l If four moles of a compound are formed from its elements in their standard states, then the standard enthalpy of formation value must be multiplied by 4 to get th ...
A Model For the Calculation of Solvent ... Reaction Rates for Process Design Purposes
... solvents be chosen with respect not only to their effectiveness in their respective process tasks but also for process-wide requirements such as their ease of recovery, low toxicity and environmental impact and possible applicability to other process tasks. Although there are models for the evaluati ...
... solvents be chosen with respect not only to their effectiveness in their respective process tasks but also for process-wide requirements such as their ease of recovery, low toxicity and environmental impact and possible applicability to other process tasks. Although there are models for the evaluati ...
Peptide bond formation by aminolysin
... 2.0 mM L-Phe-OMe as the acyl donor and 25.0 mM L-Phe as the acyl acceptor were subjected to aminolysin-A catalysis under several pH conditions. The reaction proceeded efficiently under basic pH to give L-Phe-L-Phe as the major product; however, the yield rapidly decreased at pH 10.0. The reason for t ...
... 2.0 mM L-Phe-OMe as the acyl donor and 25.0 mM L-Phe as the acyl acceptor were subjected to aminolysin-A catalysis under several pH conditions. The reaction proceeded efficiently under basic pH to give L-Phe-L-Phe as the major product; however, the yield rapidly decreased at pH 10.0. The reason for t ...
Stoichiometry
Stoichiometry /ˌstɔɪkiˈɒmɨtri/ is the calculation of relative quantities of reactants and products in chemical reactions.Stoichiometry is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers. This means that if the amounts of the separate reactants are known, then the amount of the product can be calculated. Conversely, if one reactant has a known quantity and the quantity of product can be empirically determined, then the amount of the other reactants can also be calculated.As seen in the image to the right, where the balanced equation is:CH4 + 2 O2 → CO2 + 2 H2O.Here, one molecule of methane reacts with two molecules of oxygen gas to yield one molecule of carbon dioxide and two molecules of water. Stoichiometry measures these quantitative relationships, and is used to determine the amount of products/reactants that are produced/needed in a given reaction. Describing the quantitative relationships among substances as they participate in chemical reactions is known as reaction stoichiometry. In the example above, reaction stoichiometry measures the relationship between the methane and oxygen as they react to form carbon dioxide and water.Because of the well known relationship of moles to atomic weights, the ratios that are arrived at by stoichiometry can be used to determine quantities by weight in a reaction described by a balanced equation. This is called composition stoichiometry.Gas stoichiometry deals with reactions involving gases, where the gases are at a known temperature, pressure, and volume and can be assumed to be ideal gases. For gases, the volume ratio is ideally the same by the ideal gas law, but the mass ratio of a single reaction has to be calculated from the molecular masses of the reactants and products. In practice, due to the existence of isotopes, molar masses are used instead when calculating the mass ratio.