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@X@user.full_name@X@ @GMU: What is the empirical formula of a compound if its percent composition is 68.74% C and 12.18% H and 8.907% N ? The compound contains only C, H, N and O.

@X@user.full_name@X@ @GMU: What is Kp for the reaction below, if Kc = 1.78e-5 at 153.5°C?4A(s) + 4B(g) → 5C(g)

@X@user.full_name@X@ @GMU: ACS-Determine the cell potential for the reaction below if [Cd2+] = 0.2140M and [Fe3+] = 0.0105M 3Cd2+(aq) + 2Fe(s) → 3Cd(s) + 2Fe3+(aq) E°= -0.360V

@X@user.full_name@X@ @GMU: What is the balanced reaction for the following galvanic cell?Cd(s)| Cd2+(aq) || Pb2+(aq) | Pb(s)

@X@user.full_name@X@ @GMU: What is the mass (grams) of one molecule of CH4?

@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 15.20 g of kaolinite?

@X@user.full_name@X@ @GMU: A gas mixture contains an unknown amount of Xe and 0.1092 mol of C3H8. How many moles of Xe are there, if the total pressure is 841.48 mm Hg and the partial pressure of Xe is 519.69 mm Hg?

@X@user.full_name@X@ @GMU: A compound contains only calcium and chlorine. A sample weighing 6.71 g of this compound contained 2.42 g of calcium. How many grams of chlorine would there be in another sample of this compound containing 7.59 g of calcium?

The #1 neurotransmitter responsible for depression is: 

@X@user.full_name@X@ @GMU: Using bond energies from the table, estimate ΔH for the reaction below. The product has a fluorine atom bound to each carbon.CH2=CH2(g) + F2(g) → CH2FCH2F(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