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How many atoms of hydrogen are involved in the formation of two molecules of water as depicted by this chemical equation 2h2 + O2 = 2h2O?
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A) calculate the ph of a buffer that is 0.190 m in nahco3 and 0.190 m in na2co3. (see the dissociation constants for acids table.) (b) calculate the ph of a solution formed by mixing 26. ml of 0.30 m
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Concept question (10 points) 1. predict the product. provide the stable organic product(s) for the reactions below.
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Bromination of an alkene by n-bromosuccinimide (nbs) in the presence of light or peroxide is a radical reaction and produces an allylic bromide. for the bromination of 3-methylcyclopentene, select the
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Use the standard free energy given in the above reaction to calculate equilibrium constant kp at 25c for the reaction
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The preexponential and activation energy for the diffusion of chromium in nickel are 1.1 × 10-4 m2/s and 272,000 j/mol, respectively. at what temperature (in ˚c) will the diffusion coefficient have
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You can practice converting between the mass of a solution and mass of solute when the mass percent concentration of a solution is known. the concentration of the kcn solution given in part a correspo
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When ethylbenzene is treated with nbs and irradiated with uv light, two stereoisomeric compounds are obtained in equal amounts. draw the products and explain why they are obtained in equal amounts:?
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Both Josef Loschmidt and Amedeo Avogadro contributed to our understanding of basic molecular numbers, sizes, and reaction ratios. Neither scientist discovered “Avogadro’s number” in the form we
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In the balanced reaction between sodium borohydride and hydrochloric acid, bh4- + h+ + y h2o → x h3bo3 + z h2 (g) what is the value of the coefficient of water, y?
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Chemistry
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Which of the following would you predict to have a positive value for º? AgCl(s) → Ag+(aq) + Cl-(aq) H2O(g) → H2O(l) 2 Na(s) + Cl2(g) → 2NaCl(s) Br2(l) → Br2(s)
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Research face-centered cubic structures on the web. what is the length of one side of the crystal unit cell for aluminum? (show your work)
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If you have two samples that have the same mass but are composed of different elements, what can you conclude?
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If 2 grams of element x combine with 4 grams of element y to form compound xy , how many grams of element x would combine with 28 grams of element y to form the same compound
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Question 13 (Essay Worth 10 points) (03.02 HC) Use the portion of the periodic table shown below to answer the questions. A portion of the first three columns of the periodic table is shown. Column
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If two solutions with concentrations of 0.5 M sugar and 0.9 M sugar respectively are separated by a semipermeable membrane, during osmosis there is a net flow of: 1. Sugar molecules from the concentra
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How many moles of aqueous potassium ions and sulfate ions are formed when 62.4 g of K2SO4 dissolves in water?
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Consider the location of barium, chlorine, iodine, and strontium on the periodic table.Which type of atom has the strongest attraction for electrons in bond formation?
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Which statement best describes the energy of activation? It is not affected by a catalyst. It is lower if the reaction temperature decreases. It is higher if the reaction temperature increases. It is
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If some neon gas at 0.75 atm were allowed to expand from 3.7L to 6.0L without changing the temperature, what pressure would the neon gas exert under these new conditions?
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Dentify whether each process is endothermic or exothermic. drag the appropriate items to their respective bins.identify the possible sign(s) for an endothermic process.
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A voltaic cell is constructed by connecting a nickel electrode that is dipped into 1.20 m niso4 solution to a chromium electrode that is dipped into a solution containing cr3+ at an unknown concentrat
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Spearmint oil can be produced by steady state extraction with hexane one such process is shown below where a solids free extract is produced and 15 percentof teh oil in the feed
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What substance could you add to each solution to make it a buffer solution? you may want to reference ( page ) section 14.10 while completing this problem. part a 0.050 m nahso3?
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When 50.0 ml of 1.20 m of hcl(aq) is combined with 50.0 ml of 1.30 m of naoh(aq) in a coffee-cup calorimeter, the temperature of the solution increases by 8.01°c. what is the change in enthalpy for t
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One naturally occurring terpene molecule is α-pinene that contains 2-methyl-2,3-butadiene, or isoprene, units. highlight the isoprene carbon skeleton in α-pinene by clicking on the bonds, not the at
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Please SHOW your work. #1 to #5. I need exact answer.
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What is the biggest disadvantage of solar electricity, or at least, why is it not used much more than it currently is? A.Carbon dioxide emissions B.Leads to water and air pollution C.Not renewable D.V
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The density for potassium is 0.856 g/cm3. What would be the mass of a 30 cm3 piece of potassium? A. 51.36g B. 25.68g C. 25.5g D. 35.05g
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What volume of steam at 100◦C and 1.00 atm would, during condensation, release the same amount of heat as 81.0 cm3 of liquid water during freezing?
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The average propane cylinder for a residential grill holds approximately 18 kg of propane. how much energy (in kj) is released by the combustion of 20.00 kilograms of propane in sufficient oxygen?
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Which of the following is not used to perform experiments with liquids? a. beakers b. flasks c. graduated cylinders d. rulers
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Is it true or false that scientists have identified shadow zones in the earths interior. One cause of the shadow zone results from S-waves being unable to transmit through the liquid core .
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Select Earthquakes and Major Plates on the World Geology map and observe earthquake activity around the South American plate. Based on your observations, what can you conclude about lithospheric motio
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An acceleroneter is a device that use the extension of a spring to measure acceleration in terms of Earth's gravitational acceleration (g). What is the approximate acceleration if this accelerometer s
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How is electronegativity related to covalent bonding? Atoms must have similar electronegativities in order to share electrons in a covalent bond. Atoms must have very different electronegativities in
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If 8.00 L of water vapor at 50.2 °C and 0.121 atm reacts with excess iron, how many grams of iron(III) oxide will be produced? 2Fe+3H2O=Fe2O3+3h2
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A sealed container was filled with 0.300 mol h2(g), 0.400 mol i2 (g), and 0.200 mol hi (g) at 870k and total pressure 1.00 bar. calculate the amounts of the components in the mixture at equilibrium gi
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Calculate the electrical energy per gram of anode material for the following reaction at 298 K: Li(s) + MnO2(s) ----> LiMnO2(s) Ecell = 3.15 V
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Aqueous lithium sulfate was mixed with aqueous strontium chlorate, and a crystallized strontium sulfate product was formed. Consider the other product and its phase, and then write the balanced molecu
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I need a final draft for this Lab Report. Please read this and make it perfect. My Professor wrote something on the paper. Please fix it and add it. and please add more information on it. Please
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sample of an ideal gas has a volume of 2.25 L at 282 K and 1.15 atm. Calculate the pressure when the volume is 1.36 L and the temperature is 298 K.
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Although Rutherford is credited with the famous gold foil scattering experiment, he didn’t actually conduct this experiment himself. It was done by two of his assistants, Hans Geiger and Ernest Mars
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Which of the following is an example of a conversion from electrical energy to sound energy? microphone radio generator windmill
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All of the following are indicators of chemical change except… a. Change in color b. Production of a gas c. Formation of a precipitate d. All of the above are indicators of chemical change
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Pb(NO3)2 (aq) + 2KI (aq) ——> PbI2 (s) + 2KNO3 (aq) what type of reaction the following chemical equations represent.
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For the reaction 2HNO₃ + Mg(OH)₂ ---> Mg(NO₃)₂+2H₂O how many moles of magnesium nitrate are produced from 143.2 grams nitric acid, HNO₃?
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Use kinetic-molecular theory to describe what happens when an ice cube or icicle melts. Include how energy is involved and what happens to the motion of the water molecules
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Complete this equation for the dissociation of na2co3(aq). omit water from the equation because it is understood to be present.
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A sealed vessel initially contains only CO2 and CaCO3 if the temperature remains at 215K and the volume remains at 1.6L while the reactions occurs will the pressure increase decrease or remain the sam
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