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B1  (Show your work on your Free Response Paper for full credit) At 25°C, the following heats of reaction are known:   ∆H (kJ/mol) 2ClF + O2 –> Cl2O + F2O 167.4 2ClF3 + 2O2 –> Cl2O + 3F2O 341.4 2F2 + O2 –> 2F2O –43.4 At the same temperature, calculate ∆H for the reaction: ClF + F2 –> ClF3

Fe has __________ that is (are) unpaired in its d orbitals.

Nitric acid, HNO3, was first prepared 1200 years ago by heating naturally occurring sodium nitrate (called saltpeter) with sulfuric acid to produce sodium bisulfate and collecting the vapors of HNO3 produced.  Calculate DH°rxn for this reaction.  ∆H°f[NaNO3(s)] = -467.8 kJ/mol; ∆H°f[NaHSO4(s)] = -1125.5 kJ/mol; ∆H°f[H2SO4(l)] = -814.0 kJ/mol; ∆H°f[HNO3(g)] = -135.1 kJ/mol.NaNO3(s)  +  H2SO4(l)  =>   NaHSO4(s) + HNO3(g)

A 32.5 g piece of aluminum (which has a molar heat capacity of 24.03 J/°C·mol) is heated to 82.4°C and dropped into a calorimeter containing water (specific heat capacity of water is 4.18 J/g°C) initially at 22.3°C. The final temperature of the water is 24.2°C. Ignoring significant figures, calculate the mass of water in the calorimeter.

A chunk of lead at 91.6°C was added to 200.0 g of water at 15.5°C. The specific heat of lead is 0.129 J/g°C, and the specific heat of water is 4.18 J/g°C. When the temperature stabilized, the temperature of the mixture was 17.9°C. Assuming no heat was lost to the surroundings, what was the mass of lead added?

Choose the element with the highest ionization energy.

B2  (Show your work on your Free Response Paper for full credit) Using the following thermochemical data: 2Cr(s) + 6HF(g) –> 2CrF3(s) + 3H2(g) ∆H° = –691.4 kJ/mol 2Cr(s) + 6HCl(g) –> 2CrCl3(s) + 3H2(g) ∆H° = –559.2 kJ/mol calculate ∆H° for the following reaction:CrF3(s) + 3HCl(g) –> CrCl3(s) + 3HF(g)

To find mentions of their brand across social media platforms, digital marketers can make use of a practice known as:

“Owned” and “Unowned” media should all be listed on one page of the audit spreadsheet.

Which of the following are advantages of a corporation? Choose all that apply.