Which of these Lewis structures represent the BEST Lewis structure of the possible Lewis structures for each of the compounds shown? (I. PCl₅ II. SO₃ III. XeF₄)

40. In a chemical reaction, the value of ΔH differs from the ΔE value at constant T and P when

The ideal gas law is most valid when the assumptions of the kinetic molecular theory of gases hold. One of these assumptions is that there are no interactions between the individual particles in the gas phase. Under what pressure conditions would this assumption best hold?

Which of the following cations has the SMALLEST radius?

54. Would you predict a large ΔS°, either positive or negative, for the thermite reaction? Choose the best answer and justification.

The unique H-bonding characteristics of water make it especially interesting. All of the following are true characteristics of water EXCEPT

50. That same 0.25 g sample of isopentane (molar mass 72.15 g/mol) boils when it is spread on skin at 37.0 °C. Assuming ideal gas behavior at 1.00 atm, what volume does the resulting vapor occupy?

42. Which formula/name pair from the rocket booster reaction is INCORRECT?

If a solid molecular compound has a relatively high melting point, most likely the

If the concentration of OH⁻ is 1 × 10⁻² M, the pH of the solution is