NC Exam Questions - Rosshall Academy
... (b) In what way does the structure of a fat molecule differ from that of an oil molecule? (1) (c) Over time, open containers of olive oil develop a rancid flavour. What substance is reacting with the oil to cause these unwanted changes to take place? (1) 16. A student writes the following statement. ...
... (b) In what way does the structure of a fat molecule differ from that of an oil molecule? (1) (c) Over time, open containers of olive oil develop a rancid flavour. What substance is reacting with the oil to cause these unwanted changes to take place? (1) 16. A student writes the following statement. ...
Simulations of Si and SiO2 Etching in SF6+O2 Plasma
... Six primary processes occur during a plasma etching: (1) generation of reactive species, (2) diffusion to surface, (3) adsorption, (4) reaction, both chemical and physical (such as sputtering), (5) desorption, and (6) diffusion into bulk gas. If any of them does not occur, the entire processing stop ...
... Six primary processes occur during a plasma etching: (1) generation of reactive species, (2) diffusion to surface, (3) adsorption, (4) reaction, both chemical and physical (such as sputtering), (5) desorption, and (6) diffusion into bulk gas. If any of them does not occur, the entire processing stop ...
MATTER-Ch. 3-homogeneous vs. heterogeneous, elements
... a. always more than the total mass of the products. b. always less than the total mass of the products. c. sometimes more and sometimes less than the total mass of the products. d. always equal to the total mass of the products. ____ 36. A chemical equation is balanced when the a. coefficients of th ...
... a. always more than the total mass of the products. b. always less than the total mass of the products. c. sometimes more and sometimes less than the total mass of the products. d. always equal to the total mass of the products. ____ 36. A chemical equation is balanced when the a. coefficients of th ...
MOLECULAR FORMULAS N C H H C N H HHH HH
... 4. (9 points) Gold, Au, is dissolved from rock by treating the rock with NaCN in the presence of oxygen. 4 Au(s) + 8 NaCN(aq) + O2(g) + 2 H2O(l) → 4 NaAu(CN)2(aq) + 4 NaOH(aq) (a) If you have 0.050 mol of gold, the number of moles of NaCN required is __________ mol and the number of moles of O2 requ ...
... 4. (9 points) Gold, Au, is dissolved from rock by treating the rock with NaCN in the presence of oxygen. 4 Au(s) + 8 NaCN(aq) + O2(g) + 2 H2O(l) → 4 NaAu(CN)2(aq) + 4 NaOH(aq) (a) If you have 0.050 mol of gold, the number of moles of NaCN required is __________ mol and the number of moles of O2 requ ...
SCH 3U - mquagliaoths
... All of these questions have answers in the back of the textbook except for page 212 #42. So here is its answer: i) decomposition – a compound is broken down into smaller parts; only one reactant is present ii) synthesis – the opposite of decomposition in that 2 (or more) reactants come together to m ...
... All of these questions have answers in the back of the textbook except for page 212 #42. So here is its answer: i) decomposition – a compound is broken down into smaller parts; only one reactant is present ii) synthesis – the opposite of decomposition in that 2 (or more) reactants come together to m ...
Lecture 22: Related rates
... I will illustrate the basic steps in related rates with the following problem. Problem. Suppose that a disc of very hot metal is slowly flattening out. As it flattens, it is always shaped like a cylinder. Suppose that at some instant, the cylinder is 3cm in height, with a radius of 3cm. Suppose also ...
... I will illustrate the basic steps in related rates with the following problem. Problem. Suppose that a disc of very hot metal is slowly flattening out. As it flattens, it is always shaped like a cylinder. Suppose that at some instant, the cylinder is 3cm in height, with a radius of 3cm. Suppose also ...
Kinetics of the fading of phenolphthalein in alkaline solution
... to Beer's law, the spectral absorbance of the solution is directly proportional to [P2-1, or [P2-] = constant X (ahsorhance), so ln[P2-] = In (constant) In (ahsorhance). Therefore, a plot of in (absorbance) versus time should also be a straight line with slope of - k l , if the reaction is pseudo fi ...
... to Beer's law, the spectral absorbance of the solution is directly proportional to [P2-1, or [P2-] = constant X (ahsorhance), so ln[P2-] = In (constant) In (ahsorhance). Therefore, a plot of in (absorbance) versus time should also be a straight line with slope of - k l , if the reaction is pseudo fi ...
CHEM 400 - El Camino College
... over a couple of topics from Chapter 11 and will do the lab check out before the exam.) The exam will have two parts: multiple choice questions and open-end questions. You will need to bring a Scantron form No. 882-E. Partial credit will be given for open-end questions only. Open-end questions will ...
... over a couple of topics from Chapter 11 and will do the lab check out before the exam.) The exam will have two parts: multiple choice questions and open-end questions. You will need to bring a Scantron form No. 882-E. Partial credit will be given for open-end questions only. Open-end questions will ...
AP Chemistry Syllabus – Joliet Township High School
... The laboratory activities are comprised of “hands-on” labs so the students can accomplish multiple trials and can use statistical analysis to derive conclusions. Students are required to have a bound composition book and a three ring binder, which will be used as their lab portfolio. A minimum of 25 ...
... The laboratory activities are comprised of “hands-on” labs so the students can accomplish multiple trials and can use statistical analysis to derive conclusions. Students are required to have a bound composition book and a three ring binder, which will be used as their lab portfolio. A minimum of 25 ...
Penny Sandwiches - Terrific Science
... Expected Student Responses to Exploration Step 1 (a) Bubbles should be visible in both containers. (b) The formation of bubbles indicates a chemical process (reaction). (c) The bubbles are of hydrogen gas. Step 2 (a) Bubbles should be visible while the reaction continues. The zinc interior dissolves ...
... Expected Student Responses to Exploration Step 1 (a) Bubbles should be visible in both containers. (b) The formation of bubbles indicates a chemical process (reaction). (c) The bubbles are of hydrogen gas. Step 2 (a) Bubbles should be visible while the reaction continues. The zinc interior dissolves ...
3 - Greene County ESC
... motion and vibrations of atoms and molecules. Recognize that the higher the temperature, the greater the average atomic or molecular motion, and during changes of state the temperature remains constant. 14. Summarize how nuclear reactions convert a small amount of matter into a large amount of energ ...
... motion and vibrations of atoms and molecules. Recognize that the higher the temperature, the greater the average atomic or molecular motion, and during changes of state the temperature remains constant. 14. Summarize how nuclear reactions convert a small amount of matter into a large amount of energ ...
Classifying Chemical Reactions by What Atoms Do
... Acid-Base Titrations The difficulty is determining when there has been just enough titrant added to complete the reaction. In acid-base titrations, because both the reactant and product solutions are colorless, a chemical (indicator) is added that changes color when the solution undergoes large cha ...
... Acid-Base Titrations The difficulty is determining when there has been just enough titrant added to complete the reaction. In acid-base titrations, because both the reactant and product solutions are colorless, a chemical (indicator) is added that changes color when the solution undergoes large cha ...
Standards Practice
... 11:1Students know chemical bonds between atoms in molecules such as Hz , CH4, NH3, HzCCHz , Nz, Clz, and many large biological molecules are covalent. 5. Which do not form covalent bonds? A. diatomic molecules B. large biological molecules C. molecules containing carbon D. salts 6. The bonds found i ...
... 11:1Students know chemical bonds between atoms in molecules such as Hz , CH4, NH3, HzCCHz , Nz, Clz, and many large biological molecules are covalent. 5. Which do not form covalent bonds? A. diatomic molecules B. large biological molecules C. molecules containing carbon D. salts 6. The bonds found i ...
Scientific Measurement
... How much heat is needed to melt 20 g of ice at 0˚C? q = mHf q = 20(334) = 6,680 J (Hf on Table B, don’t plug in temp.) How many grams of water can be heated by 15˚C using 13,500 J of heat? q = mC∆T 13,500 = m(4.18)(15) = 215 g It takes 5,210 J of heat to melt 50 g of ethanol at its melting point. Wh ...
... How much heat is needed to melt 20 g of ice at 0˚C? q = mHf q = 20(334) = 6,680 J (Hf on Table B, don’t plug in temp.) How many grams of water can be heated by 15˚C using 13,500 J of heat? q = mC∆T 13,500 = m(4.18)(15) = 215 g It takes 5,210 J of heat to melt 50 g of ethanol at its melting point. Wh ...
Spectroscopy and Statistical Thermodynamics: Revisiting the HCl
... macroscopic system containing one mole of molecules. In the case of entropy, we are concerned with the number of ways the system can be arranged at a particular temperature. Therefore, instead of considering the molecules individually, we consider a collection of replications of the system, which al ...
... macroscopic system containing one mole of molecules. In the case of entropy, we are concerned with the number of ways the system can be arranged at a particular temperature. Therefore, instead of considering the molecules individually, we consider a collection of replications of the system, which al ...
Questions 3-4 from AP exam 2006
... (iii) Calculate the value of the equilibrium constant, Ksp . (b) A saturated solution is prepared by adding PbI2(s) to distilled water to form 2.0 L of solution at 25°C. What are the molar concentrations of Pb2+ (aq) and I −(aq) in the solution? Justify your answer. (c) Solid NaI is added to a satur ...
... (iii) Calculate the value of the equilibrium constant, Ksp . (b) A saturated solution is prepared by adding PbI2(s) to distilled water to form 2.0 L of solution at 25°C. What are the molar concentrations of Pb2+ (aq) and I −(aq) in the solution? Justify your answer. (c) Solid NaI is added to a satur ...
Transition state theory
Transition state theory (TST) explains the reaction rates of elementary chemical reactions. The theory assumes a special type of chemical equilibrium (quasi-equilibrium) between reactants and activated transition state complexes.TST is used primarily to understand qualitatively how chemical reactions take place. TST has been less successful in its original goal of calculating absolute reaction rate constants because the calculation of absolute reaction rates requires precise knowledge of potential energy surfaces, but it has been successful in calculating the standard enthalpy of activation (Δ‡Hɵ), the standard entropy of activation (Δ‡Sɵ), and the standard Gibbs energy of activation (Δ‡Gɵ) for a particular reaction if its rate constant has been experimentally determined. (The ‡ notation refers to the value of interest at the transition state.)This theory was developed simultaneously in 1935 by Henry Eyring, then at Princeton University, and by Meredith Gwynne Evans and Michael Polanyi of the University of Manchester. TST is also referred to as ""activated-complex theory,"" ""absolute-rate theory,"" and ""theory of absolute reaction rates.""Before the development of TST, the Arrhenius rate law was widely used to determine energies for the reaction barrier. The Arrhenius equation derives from empirical observations and ignores any mechanistic considerations, such as whether one or more reactive intermediates are involved in the conversion of a reactant to a product. Therefore, further development was necessary to understand the two parameters associated with this law, the pre-exponential factor (A) and the activation energy (Ea). TST, which led to the Eyring equation, successfully addresses these two issues; however, 46 years elapsed between the publication of the Arrhenius rate law, in 1889, and the Eyring equation derived from TST, in 1935. During that period, many scientists and researchers contributed significantly to the development of the theory.