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@X@user.full_name@X@ @GMU: Using bond energies from the table, estimate ΔH for the reaction below.N2F4(g) → N2F2(g) + F2(g) Bond Energies, kJ/mol Single Bonds   H C N O S F Cl Br I H 432                 C 411 346               N 386 305 167             O 459 358 201 142           S 363 272 — — 286         F 565 485 283 190 284 155       Cl 428 327 313 218 255 249 240     Br 362 285 243 201 217 249 216 190   I 295 213 — 201 — 278 208 175 149   Multiple Bonds C=C 602 C=N 615 C=O 799 CºC 835 CºN 887 CºO 1072 N=N 418 N=O 607 S=O (in SO2) 532 NºN 942 O2 494 S=O (in SO3) 469

@X@user.full_name@X@ @GMU: What is the correct name for In2S3?

@X@user.full_name@X@ @GMU: What is the free energy change at 25°C for the reaction below, if ΔGfo(CH4(g) = -50.790 kJ/mol, ΔGfo(C8H18(g)) is 17.379 kJ/mol.C8H18(g) + 7H2(g) → 8CH4(g)

@X@user.full_name@X@ @GMU: Kaolinite, a clay mineral with the formula Al4Si4O10(OH)8, is produced naturally by the chemical weathering of aluminum silicate minerals like feldspar (granite). Kaolinite is used industrially as filler in slick-paper for magazines and as a raw material for ceramics. How many grams of oxygen are present in 16.27 g of kaolinite?

Nitric oxide, NO, is made from the oxidation of NH3 and the reaction is represented by the equation a NH3 + b O2 –> c NO + d H2O In the balanced equation, the correct coefficients for a, b, c, d are

@X@user.full_name@X@ @GMU: ACS-Using the given rate data what is the correct rate law for the reaction below?2NO + O2 ⇋ 2NO2  Exp [NO]o [O2]o Initial Rates, Ms-1 1 0.156 0.156 2.70e1 2 0.312 0.156 1.08e2 3 0.312 0.228 1.58e2

@X@user.full_name@X@ @GMU: A compound contains only strontium and fluorine. A sample weighing 2.76 g of this compound contained 1.93 g of strontium. How many grams of fluorine would there be in another sample of this compound containing 4.99 g of strontium?

@X@user.full_name@X@ @GMU: Closed-tube manometers work exactly as barometers except by connecting them to a container its pressure can be measured. Assume you have a closed-ended manometer filled with an oil having a density of 0.7958 g/mL at 20°C rather than mercury (density = 13.546 g/mL at 20°C). What is the pressure if the height of the oil column is 1126.49 cm?

@X@user.full_name@X@ @GMU: Kaolinite, a clay mineral with the formula Al4Si4O10(OH)8, is produced naturally by the chemical weathering of aluminum silicate minerals like feldspar (granite). Kaolinite is used industrially as filler in slick-paper for magazines and as a raw material for ceramics. How many grams of oxygen are present in 14.64 g of kaolinite?

@X@user.full_name@X@ @GMU: Determine the rate of formation of I3− if the initial concentration of I− was 0.4044 M and decreased to 0.3183 M after 0.2340 hours. Use the reaction below.3I−(aq)+ S2O82−(aq) → I3−(aq) + 2SO42−(aq)