Limestone stalactites and stalagmites are formed in caves bythe following reaction:Ca2+ (aq) + 2 HCO3-(aq) ---->CaCO3(s) + CO2(g) + H2O(l)If 1 mol of CaCO3 forms at 298 K under 1 atm pressure, thereaction performs 2.47 kJ of P–V work, pushing back the atmosphereas the gaseous CO2 forms. At the same time, 38.95 kJof heat is absorbed from the environment. What are thevalues of ΔH and of ΔE for this reaction?

Calculate ΔH for the reaction (1) 2C (s, graphite) + H2(g) --> C2H2(g). given the following chemical equations and their respective enthalpy changes: (2) C2H2 + 5/2 O2(g) ---> 2CO2(g)+H2O(l)  ΔH = -1299.6 KJ/mol (3) C(s, graphite) + O2(g) --> CO2(g)    ΔH = -393.5 KJ/mol (4) H2 (g) + 1/2 O2(g) --> H2O(l)   ΔH = -285.8 KJ/mol

1. Given the following thermochemical data at 25°C and 1 atm pressure, 3 202(g) + 2B(s) → B203(s) AH° =-1264 kJ O3(g) + 2B(s) → B2O3(s) AH° = -1406 kJ determine AH° for the following reaction at 25°C and 1 atm pressure. 203(g) → 302(g)

Write a balanced chemical equation for the formation of NH3(g) from N₂(g) and H₂(g). (Use the lowest possible coefficients. Be sure to specify states such as (aq) or (s). If a box is not needed, leave it blank.) Calculate AG at 522 K for the formation of 1.00 mol of NH3(g). A, GⓇ Kp + Compound AfH (kJ/mol) S (J/K mol) N₂(g) H₂(g) NH3(g) = = Use AG' value to calculate K, for the equilibrium. kJ 0 → 0 -45.90 191.56 130.7 192.77