A sample of pure solid naphthalene (C10H8) weighing 0.6410 g is burned completely with oxygen to CO2(g) and H2O(,) in a constant-volume calorimeter at 25°C. The amount of heat evolved is observed to be 25.79 kJ. (a)  Write and balance the chemical equation for the combustion reaction. (b)  Calculate the standard change in internal energy (DU°) for the combustion of 1.000 mol naphthalene to CO2(g) and H2O(,). (c)  Calculate the standard enthalpy change (DH°) for the same reaction as in part (b).

12.00 g of Compound with molecular formula C4h8 are burned in a constant-pressure calorimeter containing 15.00 kg of water at 25 °C. The temperature of the water is observed to rise by 8.603 °C. (You may assume all the heat released by the reaction is absorbed by the water, and none by the Calculate the standard heat of formation of Compound X at 25 °C. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits. calorimeter itself.)

When 1.0 mol N204(g) is formed from 2.0 mol NO2(g) under constant pressure (1 atm) at 298 K, please calculate:(a) the reaction enthalpy (ArH) of this reaction according to the standard molar formation enthalpy of NO2(g) and N204(g)at 298 K, +33.85 kJ/mol and +9.66 kJ/mol, respectively.(b) the entropy change in the surrounding. (hint: equal to the heat received by surrounding / temperature of thesurrounding)

(b) The standard enthalpy change for the following reaction is -697 kJ at 298 K.2 Zn(s) + O2(g)2 ZnO(s)What is the standard heat of formation of ZnO(s)

1 If the standard enthalpy of cembustion of gaseous cyclopropane, C3H6, is -2091.2 kJ mol- at 25 C, calculate the standard enthalpy of formation of the compound at 298 K. (The standard enthalpy of combustion is the heat of combustion of one mole of a compound to the most stable combustion products, which are CO2(g) and H20(1) in the case of hydrocarbons. The standard enthalpy of formation is the enthalpy of formation of one mole of a compound from its constituent elements, the compound and its constituent elements in their standard states.)

(b) What is the specific enthalpy of combustion of ethane? kJ/g. 3 sig. number.

The enthalpy of combustion of benzoic acid (C,H,COOH) is commonly used as the standard for calibrating constant-volume bomb calorimeters; its value has P mol been accurately determined to be -3226.7 - When 2.5311 g of benzoic acid are burned in a calorimeter, the temperature rises from 20.84 °C to 26.67 °C. What is the heat capacity of the bomb? (Assume that the quantity of water surrounding the bomb is exactly 2250 g) Round your answer to 3 significant digits. Note: Reference the Phase change properties of pure substances table for additional information. 0-/2 0.8 X 5 8 @ al P

A 25.0 mL portion of dilute HCl (aq) is combined with a 25.0 mL portion of dilute NaOH in a coffee-cup calorimeter. Both solutions are initially at a temperature of 23.3 ºC. The reaction produces enough heat to raise the final temperature of the 50.0 mL of liquid in the calorimeter to 25.3 ºC . What is qrxn in J? Assume the density of the reaction mixture is 1.0 g/mL and the specific heat of the solution is 4.184 J/g· ºC