8. Thermochemistry

Which of the following represents the formation equation for barium nitrate, Ba(NO₃)₂?

Identify a substance that is not in its standard state.

Ibuprofen is used as an anti-inflammatory agent used to deal with pain and bring down fevers. If it has a molecular formula of C₁₃H­₁₈O₂, determine the balanced chemical equation that would give you directly the enthalpy of formation for ibuprofen. 

(c) What is meant by the term standard enthalpy of formation?

(a) Why does the standard enthalpy of formation of both the very reactive fluorine (F₂) and the almost inert gas nitrogen (N₂) both read zero?

For each of the following compounds, write a balanced thermochemical equation depicting the formation of one mole of the compound from its elements in their standard states and then look up ΔH°_f for each substance in Appendix C. (a) NO₂(g) (b) SO₃(g) (c) NaBr(s) (d) Pb(NO₃)₂(s).

Write balanced equations that describe the formation of the following compounds from elements in their standard states, and then look up the standard enthalpy of formation for each substance in Appendix C: (a) CH₃OH(l)