Which is a formation enthalpy: a) Na+(aq) + NO3-(aq) → NaNO3(aq) b) Na+(g) + NO3-(g) → NaNO3(s) c) Na(s) + NO3(s) → NaNO3(s) d) 2Na(s) + N2(g) + 3O2(g) → NaNO3(s) e) Na(s) + 1/2 N2(g) + 3/2O2(g) → NaNO3(s)

Nitric oxide (NO) can be formed from nitrogen, hydrogen and oxygen in two steps. In the first step, nitrogen and hydrogen react to form ammonia: N₂(g) + 3H₂(g) 2 NH3(g) In the second step, ammonia and oxygen react to form nitric oxide and water: 4 NH3(g) + 50₂(g) → 4 NO(g) + 6 H₂O(g) ΔΗ = - 92. kJ kJ Calculate the net change in enthalpy for the formation of one mole of nitric oxide from nitrogen, hydrogen and oxygen from these reactions. Round your answer to the nearest kJ. X AH = -905. kJ

Thermometer In the laboratory a "coffee cup" calorimeter, or constant pressure calorimeter, is frequently used to determine the specific heat of a solid, or to measure the energy of a solution phase reaction. Stiring md A student heats 63.29 grams of nickel to 97.88 °C and then drops it into a cup containing 76.34 grams of water at 21.12 °C. She measures the final temperature to be 27.55 °C. The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.60 J/°C. Water Assuming that no heat is lost to the surroundings calculate the specific heat of nickel. Metal- sample at Specific Heat (Ni) = J/g°C. 2003 Thomwan-drookaCole ot pt Submit Answer Try Another Version 3 item attempts remaining Previous Next Save and Exit nt Cengage Learning | Cengage Technical Support MacBook Pro

When methanol, CH, OH, is burned in the presence of oxygen gas, O₂, a large amount of heat energy is released. For this reason, it is often used as a fuel in high performance racing cars. The combustion of methanol has the balanced, thermochemical equation CH₂OH(g) + O₂(g) → CO₂(g) + 2 H₂O(1) AH = -764 kJ How much methanol, in grams, must be burned to produce 983 kJ of heat? mass: g