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Which species has this ground-state electron arrangement?        1s2 2s2 2p6 3s2 3p6 3d10  Data sheet and Periodic Table

How much heat is evolved or absorbed when 25.0 g of silver oxidizes to form silver oxide (Ag2O) under standard conditions? The enthalpy of formation (ΔHfo) of Ag2O is –31.05 kJ∙mol–1 and the molar mass of silver is 107.87 g∙mol–1.   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 statement best describes the bond length(s) in the nitrite ion (shown)?  The bond length of N–O is 136 pm and N=O is 122 pm.          Data sheet and Periodic Table

For the orbital diagram shown, what is a possible set of quantum numbers for the next lowest energy electron added?        Data sheet and Periodic Table

As shown in the figure, a reaction vessel initially contains hydrogen and oxygen.  Which figure best shows the reaction once complete?                2H2(g) + O2(g)2H2O(g)                        Data sheet and Periodic Table

Using formal charges, which Lewis dot structure is correct for the carbonate ion, CO32–?   Data sheet and Periodic Table

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

What volume (in L) will 50.0 g of nitrogen gas occupy at 2.0 atm of pressure and at 65 oC? Data sheet and Periodic Table

The gases, F2, H2, N2, and O2 at STP are represented in the plot.  Which gas corresponds to curve III?                   Data sheet and Periodic Table