In an experiment, a 0.4494 g sample of pyrene ( C16H10) is burned completely in a bomb calorimeter. The calorimeter is surrounded by 1.327 × 10³ g of water. During the combustion the temperature increases from 24.64 to 27.30 °C. The heat capacity of water is 4.184 J·g¯¹. C¹. 0 The heat capacity of the calorimeter was determined in a previous experiment to be 801.8 J. ˚C-¹. Assuming that no energy is lost to the surroundings, calculate the molar heat of combustion of pyrene based on these data. C16H10 (8) + (37/2)O2(g) → 5H₂O(1) + 16CO2 (g) + Energy kJ/mol Molar Heat of Combustion =

In a bomb calorimeter, the reaction vessel is surrounded by water that must be added for each experiment. Since the amount of water is not constant from experiment to experiment, the mass of water must be measured in each case. The heat capacity of the calorimeter is broken down into two parts: the water and the calorimeter components. If a calorimeter contains 1.00 kg water and has a total heat capacity of 10.84 kJ/C, what is the heat capacity of the calorimeter components?

For the reaction HgO(s)Hg(l)+12O2(g),H=+90.7kJ: a.What quantity of heat is required to produce 1 mole of mercury by this reaction? b.What quantity of heat is required to produce 1 mole of oxygen gas by this reaction? c.What quantity of heat would be released in the following reaction as written? 2Hg(l) + O2(g) 2HgO(s)

Would the amount of heat measured for the reaction in Example 5.5 be greater, lesser, or remain the same if we used a calorimeter that was a poorer insulator than a coffee cup calorimeter? Explain your answer.

The bomb calorimeter in Exercise 102 is filled with 987 g water. The initial temperature of the calorimeter contents is 23.32C. A 1.056-g sample of benzoic acid (Ecomb = 26.42 kJ/g) is combusted in the calorimeter. What is the final temperature of the calorimeter contents?

Using the data in Appendix G, calculate the standard enthalpy change for each of the following reactions: (a) Si(s)+2F2(g)SiF4(g) (b) 2C(s)+2H2(g)+O2(g)CH3CO2H(l) (c) CH4(g)+N2(g)HCN(g)+NH3(g) ; (d) CS2(g)+3Cl2(g)CCl4(g)+S2Cl2(g)

Salicylic acid, C7H6O3, is one of the starting materials in the manufacture of aspirin. When 1.00 g of salicylic acid burns in a bomb calorimeter, the temperature of the bomb and water goes from 23.11C to 28.91C. The calorimeter and water absorb 21.9 kJ of heat. How much heat is given off when one mole of salicylic acid burns?

Consider the following reaction: CH4(g)+2O2(g)CO2(g)+2H2O(l)H=891KJ Calculate the enthalpy change for each of the following cases: a. 1.00 g methane ics burned in excess oxygen. b. 1.00 103 L methane gas at 740. torr and 25C are burned in excess oxygen. The density of CH4(g) at these conditions is 0.639 g/L.

Ammonium nitrate is an oxidizing agent and can give rise to explosive mixtures. A mixture of 2.00 mol of powdered aluminum and 3.00 mol of ammonium nitrate crystals reacts exothermically yielding nitrogen gas, water vapor, and aluminum oxide. How many grams of the mixture are required to provide 245 kJ of heat? See Appendix C for data.

Hypothetical elements A2 and B2 react according to the following equation, forming the compound AB. A2(aq)+B2(aq)2AB(aq);H=+271kJ/mol If solutions A2(aq) and B2(aq), starting at the same temperature, are mixed in a coffee-cup calorimeter, the reaction that occurs is a exothermic, and the temperature of the resulting solution rises. b endothermic, and the temperature of the resulting solution rises. c endothermic, and the temperature of the resulting solution falls. d exothermic, and the temperature of the resulting solution falls. e exothermic or endothermic, depending on the original and final temperatures.