The following data for heat output was obtained for three exothermic salts:   Salt #1: 44.6 J/¢ Salt #2: 78.5 J/¢ Salt #3: 56.9 J/¢   Which of the salts would be the best choice to use for a hot pack?

When 6.54 grams of Zn is placed in 500.0 mL of 1.00 M CuSO4(aq) in a coffee cup calorimeter, it reacts completely to displace copper. The temperature of the solution rises from 20.0˚C to 30.4˚C. Assume the coffee cup itself gains no heat and that the solution has the same density (1.00 g/mL) and specific heat (4.184 J/g˚C) as pure water. (a) How much heat does the solution gain during this reaction? (in J)

When 50 mL of 0.400 M aqueous hydrochloric acid (HCI; Molar mass: 36.5 g'mol) is mixed with 50 mL of 0.400 M aqueous sodium hydroxide (NaOH; Molar mass: 40 g/mol) in a calorimeter the temperature increases by 3.4°C. If the heat capacity of calorimeter (excluding water) is 320 Ji°C, calculate AH of neutralization reaction in kJ/mol. (Specific heat capacity of water is 4.184 J°C- gl. Density of water is 1 g'mL Assume that the heat capacity and the density of the solution is same with water) 2511 kJ/mol O A. 1.09 kJ/mol O B. 1088 kJ/mol OC. 125.5 kJ/mol OD. 2.5 kJ/mol O E.

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Which of the reactions are exothermic?

A student determines the heat of dissolution of solid potassium bromide using a coffee-cup calorimeter of negligible heat capacity.When 4.93 g of KBr(s) is dissolved in 108.00 g of water, the temperature of the solution drops from 25.00 to 23.11 °C. Based on the student's observation, calculate the enthalpy of dissolution of KBr(s) in kJ/mol. Assume the specific heat of the solution is 4.184 J/g°C.ΔHdissolution =  kJ/mol

1) A 0.416 g sample of KCl is added to 56.5 g of water in a calorimeter. If the temperature decreases by 1.24°C, what is the approximate amount of heat (in J) involved in the dissolution of the KCl, assuming the heat capacity of the resulting solution is 4.18 J/g°C? _____  J   2) Is the reaction exothermic or endothermic?

In a constant pressure coffee-cup calorimeter, 100.0 mL of 0. 050 M of Ag+ was mixed with 100.0 ml of 0.050 M of Cl‒. The temperature changed from 298.5 K to 299.4 K. Calculate the enthalpy of reaction, ΔH (kJ/mol). Assume that the solutions have a density of water (1 g/mL) and specific heat capacity of water (4.184 J/g °C).                                        Ag+(aq) + Cl‒(aq) ⟶ AgCl(s)