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Calculate the pressure exerted by 1 mol of co2 in a 1 l vessel at 300 k, assuming that that gas behaves ideally
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Assuming that the specific heat of the solution is 4.18 j/(g⋅∘c) and that the calorimeter absorbs a negligible amount of heat, calculate δh in kilojoules for the reaction naoh(aq) hcl(aq)→nacl(
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What characteristic of the species level of organization distinguishes two similar organisms such as ducks and geese as different species?
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Use the periodic table to determine the number of valence electrons in each of the following elements. Na: F: V: Ar: C:
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In a nuclear power plant, control rods are used to... Select one: a. Speed up the reaction b. Feed material to the reacion c. Slow down the reaction d. Stabilize the walls of the nuclear reactor
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Hydrogen peroxide decomposes back to water and oxygen when exposed to air and light. when bought at a pharmacy for home use, hydrogen peroxide is sold in dark bottles that are labeled as a concentrati
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A pharmacist mixes 100 ml of 38% w/w hydrochloric acid with enough purified water to make 360 ml. if the specific gravity of hydrochloric acid is 1.20, calculate the percentage strength (w/v) of the r
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Each hydrogen atom has one valence electron, but it needs two electrons to be stable. how can both hydrogen atoms each achieve a stable configuration
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Can someone help me please have a question im stuck on in my physical science class What is a medium?
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If the initial temperature is 122 k, the final temperature is 53.3k, the temperature change is what?
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Draw the two constitutionally isomeric structures formed when iodobenzene and propene are subjected to the conditions of the heck reaction. if stereoisomers are possible for a particular constitutiona
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A sample of material is found to be 32,700 years old using carbon dating. what fraction of the original remains?
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A 2.20−g sample of water is injected into an evacuated 2.00−l flask at 45.0°c. what percentage of water will be vapor when the system reaches equilibrium? assume ideal behavior of water vapor and
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Consider the reaction a(g) + b(g) <--> c(g) + d(g). you have the gases a, b, c, and d at equilibrium. upon adding gas a, the value of k:
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Be sure to answer all parts. comment on the feasibility of extracting copper from its ore chalcocite (cu2s) by heating. cu2s(s) → 2cu(s) +s(s) it is favored at low temperature. it is favored at high
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One of the crystalline forms of zinc oxide is a structure where the oxygen atoms are at the lattice points in a face-centered cubic lattice. how many atoms are in each unit cell? 10 2 4 8 6
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Luminum forms a layer of aluminum oxide when exposed to air which protects the bulk metal from further corrosion.4al(s) + 3o2(g) → 2al2o3(s)
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When elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties Mendeleev's Law the Pauli Exclusion Principle Hund's Rule Peri
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In a cathode ray experiment, electron is emitted from the surface of a negatively charged electrode, which is called ?
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A 50.88 g sample of a substance is initially at 26.1 °c. after absorbing 2159 j of heat, the temperature of the substance is 114.9 °c. what is the specific heat (sh) of the substance?
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At 20o c, the density of a 20% by mass ethanol-water solution is 968.7 kg m-3. given that the partial molar volume of ethanol in the solution is 52.2 cm3 mol-1, calculate the partial molar volume of t
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Calculate the theoretical number of moles of copper that should have plated out onto the brass piece.
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Calculate the atomic radius of iridium., given that Ir has an FFC crystal structure, a density of 22g/cm3 and atomic weight of 192.2 g/mol.
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Mc020-2.jpgH = 98.8 kJ, and mc020-3.jpgS = 141.5 J/K. Is this reaction spontaneous or nonspontaneous at high and low temperatures?
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Which statement best describes how dynamic equilibrium relates to a saturated solution of sodium chloride?
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In the hypothetical reaction below, substance A is consumed at a rate of 2.0 mol/L·s. If this reaction is at dynamic equilibrium, at what rate will substance B be consumed?
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Victor pours 100 grams of oil into a beaker filled with 1,000 grams of water. What is the total mass of his mixture? A. 100,000 grams B. 1,100 grams C. 900 grams D. 10 grams
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Victor pours 100 grams of oil into a beaker filled with 1,000 grams of water. What is the total mass of his mixture? A. 100,000 grams B. 1,100 grams C. 900 grams D. 10 grams
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Select all of the items that are true about a sample of water vapor at 101°C as it cools. A) Its temperature will fall continuously until it condensed into a liquid. B) Its temperature will fall stea
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Holly reacts 625.0 mL of 0.4899 M AgNO3 with excess Na3PO4 to form a precipitate of Ag3PO4. Calculate theoretical yield in grams
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Consider the molecule h2co. using valence bond theory, describe the location of the carbon electrons as it prepares to form bonds with the other atoms.
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A radioactive isotope of copper decays as follows: 64cu → 64zn + 0 β −1 t1/2 = 12.8 h starting with 92.0 g of 64cu, calculate the quantity of 64zn produced after 14.3 h.
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An atom is ionized so that it has only one electron. when the electron drops from the n = 3 shell to the n = 1 shell, an x-ray of wavelength 140.70 pm is emitted. what is the atomic number?
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Ammonia can be prepared by the reaction of magnesium nitride with water. the products are ammonia and magnesium hydroxide. when the equation is written and balanced, the coefficient of magnesium nitri
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A 250 milliliter sample of hydrogen was collected over water at 20◦c on a day when the atmospheric pressure was 756 torr. the vapor pressure of water under these conditions is 17.54 torr. what volum
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A freshly isolated sample of 90y was found to have an activity of 5.0 × 105 disintegrations per minute at 1:00 p.m. on december 3, 2006. at 2:15 p.m. on december 17, 2006, its activity was measured a
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Anna stated that ionic compounds have high melting points and low boiling points. She said that this demonstrates that ionic compounds have strong bonds because a lot of energy is needed to break the
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If the reaction of 5.75 moles of sodium with excess hydrofluoric acid produced an 86.5% yield of hydrogen gas, what was the actual yield of hydrogen gas? Unbalanced equation: Na + HF yields NaF + H2
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What happens when molten material travels along the underside of the crust? A. It rises up towards the crust. B. It cools and sinks towards the core. C. Lava travels away from the core and forms the c
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Which of the following could be a method used to estimate the age of an ancient rock? A. To find out its mineral composition B. To find the age of the fossils trapped in it C. To calculate the amou
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How is Earth’s surface likely to change along the edges of a bend in a river channel? A. Erosion takes place along the inner edge as water flows relatively slowly. B. Erosion takes place along the
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Which of these is an example of a physical change? A-a banana ripening in the air B-hydrogen burning in the air C-zinc reacting with an acid D-liquid water turning into vapor
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Give a sequence of reagents (inorganic or monofunctional organic with 4 or fewer carbons), in order, one per line, that will produce ch3ch2ch2c(ch3)(ch2ch3)ch=o
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What causes the appearance of lines in an emission spectrum? Light is absorbed as an electron moves to a higher energy state. Light is released as an electron moves to a lower energy state. An electro
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The electrons in the bond between hydrogen and fluorine are more strongly attracted to the bottom atom of
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Identify the combination reaction. A. C4H12+7O2 -->6H2O+4CO2 B. 2H2+O2-->2H2O C. AI2S3-->2AI+3S D. CI2+2KBr-->2KCI+Br2
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Which molecule has polar bonds that do not cancel each other out? A. Water B. Carbon Dioxide C. Fluorine gas (a diatomic molecule, F2) D. Bromine liquid (a diatomic molecule, Br2)
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Compound a has the formula c9h19cl. b is a c9h19br compound. a and b undergo base-promoted e2 elimination to give the same alkene c as the major product as well as different minor products. c reacts w
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Calculate the ph of a 0.50 m solution of sodium acetate (nach3coo) given that the ka of acetic acid (ch3cooh) is 1.8 x 10-5.
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The reaction of n−bromosuccinimide with 4−methyl−3−nitroanisole has been reported in the chemical literature. this reaction yields a single product in 95% yield. identify the product formed fr
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