What mass (in g) of iron (Fe, molar mass = 55.85 g∙mol–1) is needed to experimentally produce 50.0 g of iron(III) oxide (Fe2O3, molar mass = 159.70 g∙mol–1) in excess oxygen if the percent yield is 78.7%?                               4Fe(s) + 3O2(g)2Fe2O3(s)   Data sheet and Periodic Table

What isotope is depicted in the figure?                                      Data sheet and Periodic Table

Which pure molecular substance will have the lowest vapor pressure at 25 oC?  Data sheet and Periodic Table

What element is oxidized and what is the oxidizing agent in the reaction below?                Fe2O3(s) + 3CO(g)2Fe(s) + 3CO2(g)  Data sheet and Periodic Table

Use the given heats of formation to calculate the enthalpy change for this reaction.B2O3(g) + 3COCl2(g)2BCl3(g) + 3CO2(g)ΔHof of B2O3(g) is –1272.8 kJ∙mol–1ΔHof of BCl3(g) is –403.8 kJ∙mol–1ΔHof of COCl2(g) is –218.8 kJ∙mol–1ΔHof of CO2(g) is –393.5 kJ∙mol–1   Data sheet and Periodic Table

Which pair of particles has the same number of electrons?   Data sheet and Periodic Table

What element is oxidized and what is the oxidizing agent in the reaction below?                Fe2O3(s) + 3CO(g)2Fe(s) + 3CO2(g)  Data sheet and Periodic Table

What is the molecular geometry around the N atom in the molecule depicted?           Data sheet and Periodic Table

How many sigma (σ) and pi (π) bonds are in the molecule shown?           Data sheet and Periodic Table

What is the hybridization of the indicated nitrogen atoms?                         Data sheet and Periodic Table