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When the following equation is balanced, the coefficient in front of HCl is: Ba(s) + HCl(aq)→BaCl2(aq) + H2(g) Question 4 options: 6 1 3 2
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Quartzite and marble can look very similar. Why do you think artists carve sculptures out of marble more often then quartzite?
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A watershed, or drainage basin, is a region of land where rain or snow drains downhill into a body of water, such as a river, lake, sea, ocean or wetland. The water in drainage basins is most likely u
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PLEASE HELP 22 POINTS How does heat differ from temperature? Temperature is the measure of heat. Temperature and heat are the same thing. Temperature measures thermal energy, and heat is the flow of t
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NEED HELP PLEASE I AM GOING TO FAIL A chemical reaction has an increase in entropy and a decrease in enthalpy. What is known about the spontaneity of the reaction? spontaneous at high temperatures, no
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Two ideal gases have the same mass density and the same absolute pressure. one of the gases is helium (he), and its temperature is 181 k. the other gas is neon (ne). what is the temperature of the neo
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The boiling point of an aqueous solution is 102.30 °c. what is the freezing point? constants can be found here.
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If you know the half-life of a radioactive isotope that occurs in an igneous rock, what must you measure to determine the age of the rock?
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How long would it take to obtain a carbon concentration of 0.75 wt% at a position 0.5 mm below the surface if the heat treatment were conducted at 725 ∘c ?
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For these expressions, energies are expressed in electron volts (ev) per na+–cl– pair, and r is the distance in nanometers (nm). the net energy en is just the sum of the preceding two expressions.
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Consider the reaction 2x2y2+z2⇌2x2y2z which has a rate law of rate= k[x2y2][z2] select a possible mechanism for the reaction.
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A solution is prepared as described in part a using solid cacl2⋅2h2o and de-ionized water.mass of weighing bottle and solid before transfer: 36.683 g mass of weighing bottle and solid after transfer
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A 0.610 m aqueous solution of kbr has a total mass of 61.0 g. what masses of solute and solvent are present?
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Select the answer with the correct number of significant figures for each calculation. 31.580 + 4.26 = 35.8 35.84 35.840
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Charissa says that bread goes through a chemical change when it is toasted. Which of the following observations would least support her conclusion? A. a change in the smell of the bread B. a change in
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Investigations were carried out in a science lab to explore the topic of chemical and physical changes. Investigation A Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the s
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Please help if you have time: determine the percentage by mass of Chromium in the ore. I got the moles cro4- then divided by 2 to get moles of fe(cro2)2 because it's 4:2 ratio. Mark scheme doesn't do
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How many distinguishable slip systems are represented by {111} < 1 1 0 > in nickel at room temperature? explain?
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A voltaic cell consists of a hg/hg22+ electrode (e°= 0.85 v) and a sn/sn2+ electrode (e°= –0.14 v). calculate [sn2+] if [hg22+] = 0.24 m and ecell = 1.04 v at 25°c.
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What is the copper atoms in 1naira coin which weighs 7.39g assuming the material from which the coin is made is 86% copper.
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Calculate the volume of propylene (nu), which can be extracted from a propanol of 20 g, if the yield of the product is 87%.
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Chemistry, please help with part c only, if you have time, thanks. It's on titrations involving redox reactions.
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When 0.854 grams of a protein were dissolved in 88.9 ml of solution at 17.9 degrees c, the osmotic pressure was found to be 35.6 torr. calculate the molar mass of the protein?
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What is the boiling point of an benzene solution that freezes at 0.05 degrees c? normal freezing point is 5.5 and the normal boiling point is 80.1 degrees c. kfp = 5.12 k/m and kbp = 2.53 k/m. enter y
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Suppose instead that 5.00g ca is added to 50 ml of 1.00m hcl. determine the limiting recatant in this case and the number of moles
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Many experiments use gas manifolds to transfer gases from one reaction vessel to another. knowing the volume of such manifolds can be crucial. bulb a was filled with 540. ml of n2 gas. when opened to
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How many grams of solid magnesium nitrate (148.3 g/mol) should be added to 500 ml of 0.118 m of sodium nitrate in order to produce an aqueous 0.25 m solution of nitrate ions?
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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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