2. Cold packs take advantage of the fact that dissolving NH4NO3 in water is an endothermic process. When 5.44 g of solid ammonium nitrate is added to 150.0 g of water in a coffee cup calorimeter, the temperature of the solution changes from 18.6 °C to a final temperature which you will determine. Calculate the enthalpy change for dissolving ammonium nitrate in water, in kJ/mol. Assume the specific heat of the solution is 4.2 J/g·K. g. Using the value of qsolution, calculate ∆T, as well as the final temperature reached by the solution

A 2.74 g sample of methanol, CH3OH, is combusted in a bomb calorimeter. The temperature of the calorimeter increases by 10.1°C. If the heat capacity of the bomb is 727.1 J/°C and it contains 1200 kg of water, what is the heat evolved in kJ/mol of methanol combusted? The specific heat capacity of water is 4.184 J/g°C and the molar mass of methanol is 32.04 g/mol. Show your answer in TWO (2) decimal places.

A 2.81 g sample of methanol, CH3OH, is combusted in a bomb calorimeter. The temperature of the calorimeter increases by 11.1°C. If the heat capacity of the bomb is 727.1 J/°C and it contains 1200 kg of water, what is the heat evolved in kJ/mol of methanol combusted? The specific heat capacity of water is 4.184 J/g°C and the molar mass of methanol is 32.04 g/mol. Show your answer in TWO (2) decimal places. Do not include the units in your final answer.

22. A 44.97−g sample of water at 72.2°C is added to a sample of water at 25.7°C in a constant-pressure calorimeter. If the final temperature of the combined water is 38.4°C and the heat capacity of the calorimeter is 26.3 J/°C, calculate the mass of the water originally in the calorimeter.

A 3.000 g sample of food was then burned in a calorimeter to determine its Calories per gram content. 50mL of water were used to determine ΔT of the reaction. Initial temperature of the water at the start of the combustion reaction was 20oC, final temperature was 99oC. Calorimeter constant for this calorimeter is 10.0J/oC. How much heat has been absorbed by the water sample?

When 14.2 g KBr is dissolved in 100.0 g of water in a coffee-cup calorimeter, the temperature drops from 28.88 °C to 23.38 °C. What is the enthalpy change per gram of KBr dissolved in the water? Assume that the solution has a specific heat capacity of 4.18 J/g·K.

25.00 mL of 0.200 M sulfuric acid was added to 25.00 mL of 0.200 M NAOH, in a constant volume calorimeter. The density of the resulting solution is 1.225 g/mL and its specific heat is 5.321 J/g-°C. As the reaction took place, the temperature of the solution rose from 22.0 °C to 31.3 °C. What is AH (in units of kJ/mol) for the reaction, per mole of water formed? This is a limiting reactant problem and your choice of limiting reactant must be justified through stoichiometric calculations. 21.

1. Magnesium solid reacts with aqueous hydrochloric acid to form the Mg2+ ion in solution. In an experiment, 60.0 mL of aqueous HCl was mixed with 0.1297 g of magnesium solid in a double Styrofoam cup calorimeter. The reaction caused the temperature of the substances in the calorimeter to rise 10.02°C. Assume the density and specific heat of the HCl solution is that of water, 1.00 g/mL and 4.184 J/g °C, respectively. The specific heat of magnesium is 1.02 J/g °C. a. Write the balanced chemical equation for this reaction. b. Calculate the heat of this reaction, AHrxn, in kJ. c. Calculate the heat of this reaction per mole of Mg2+ formed, AHxn/mole Mg²+. d. The literature value of this reaction is -466.85 kJ/mole. Calculate the percent deviation of the experimental value from the literature value.

2. When solutions of an acid and a base are mixed, heat is released. Using a coffee-cup calorimeter, 100.0 mL of 0.100 mol/L HCI are mixed with 100.0 mL 0.100 mol/L NaOH solution. The initial temperature of the solutions were 22.6 °C, and the temperature after mixing was 32.4 °C. Calculate the molar enthalpy of neutralization for the reaction: HCI (aq) + NAOH (aq) → NaCI (aq) + H,0 (1)

Adding 4.88 g of NH4NO3 (s) to 140 g of water in a coffee-cup calorimeter (with stirring to dissolve the salt) resulted in a decrease in temperature from 19.0 °C to 16.7 °C. Calculate the enthalpy change for dissolving NH4NO3 (s) in water in kJ/mol. Assume the solution (whose mass is 144.9 g) has a specific heat capacity of 4.2 J/g. K. (Cold packs take advantage of the fact that dissolving ammonium nitrate in water is an endothermic process.) ACE A cold pack uses the endothermic enthalpy of a solution of ammonium nitrate. Enthalpy change = esc A kJ/mol @2 2 W S #3 E D 20 F3 $ 4 888 F4 R F do LO % 5 Cengage Learning Cengage Technical Support T G MacBook Pro 6 F6 Y v lo 7 H 38 F7 U CO DII F8 F9 K F10 L P F11 { Save and Exit F12