What initial observation led to the Alvarez asteroid-impact theory? a large undersea crater off the coast of the Yucatan Peninsula in Mexico high iridium levels in a 66-million-year-old clay layer in Denmark and Italy large concentrations of shock-fractured quartz in rock layers found in Europe dinosaur remains found near a large crater formed by an asteroid impact

Which of the following happens during cell division? (a) energy is created (b) waste is eliminated (c) carbon dioxide is released (d) damaged cells are replaced

Total number of electrons that can occupy the d sub level

Use the bond energies provided to estimate δh°rxn for the reaction below. ch3oh(l) + 2 o2(g) → co2(g) + 2 h2o(g) δh°rxn = ? bond bond energy (kj/mol) c-h 414 c-o 360 c=o 799 o=o 498 o-h 464 use the bond energies provided to estimate δh°rxn for the reaction below. ch3oh(l) + 2 o2(g) → co2(g) + 2 h2o(g) δh°rxn = ? bond bond energy (kj/mol) c-h 414 c-o 360 c=o 799 o=o 498 o-h 464 +473 kj +206 kj -392 kj -91 kj -486 kj