Consider the reaction: B2H6(g) + 3O2(g) –>B2O3(s) + 3H2O(g)             ΔH = -2035 kJ Calculate the amount of heat released when each of the following amounts of diborane (B2H6) is burned A mixture of 20.0 g B2H6 and 10.0 g O2

Nitrogen has a greater first ionization energy than oxygen. What is the best explanation for this observation?

Calculate the energy released by the reaction 4Fe(s) + 3O2(g) –> 2Fe2O3 when a 55.8 gram sample of iron reacts completely with 1.00 mol of oxygen. The enthalpy of formation (ΔH°f) of Fe2O3 (s) is -826 kj/mol.

Given the enthalpy changes: A +B –> C ΔH= -35 kj/mol A + D –> E + F ΔH= 20 kj/mol F –> C + E ΔH= 15 kj/mol

Given chemical equations for these reactions: S(s) + O2(g) –> SO2 (g) ΔH°=-296.8 kj/mol H2(g) + 1/2O2(g) –> H2O(l) ΔH°=-285.8 kj/mol H2(g) + S(s) –> H2S(g) ΔH°=-20.6 kj/mol What is the value for ΔH for the reaction below? 2H2S(g) + 3O2(g) –> 2H2O(l) + 2SO2(g)

When 30.0 ml of 0.10 M AgNO3 is added to 30.0 ml of 0.10 M NaCl, aqueous NaNO3 and solid AgCl are formed. How much solid AgCl is produced?

Vanillin, C8H8O3 (mm= 152 g/mol), is the molecule responsible for the vanilla flavor in food. How many oxygen atoms are present in 45.0 mg sample of vanillin?

Benzene, C6H6, reacts with oxygen, O2, to form CO2 and H2O. How much O2 is required for the complete combustion of 1.0 mol of C6H6?

Which element has chemical properties most similar to those of P?

100. ml of 0.220 M copper(II) chloride is mixed with 100. ml of 0.750 M sodium hydroxide.           CuCl2 + 2NaOH –> Cu(OH)2 (s) + 2NaCl What is the concentration of the negative spectator ion?