Table 4. Enthalpy of solution of salts data and calculations NHẠNO3 MgSO4 [1] Mass of salt (g) 1.991 2.000 [2] Volume of DI water (mL) 49.9 49.8 Mass of DI water (g) [3] Temperature of DI water (°C) 25.0 24.4 [4] Temperature of mixture after dissolution (°C) 21.7 32.5 Temperature difference (°C) [5] Total mass in reaction (g)

Table 4. Enthalpy of solution of salts data and calculations NHẠNO3 MgSO4 [1] Mass of salt (g) 1.991 2.000 [2] Volume of DI water (mL) 49.9 49.8 Mass of DI water (g) [3] Temperature of DI water (°C) 25.0 24.4 [4] Temperature of mixture after dissolution (°C) 21.7 32.5 Temperature difference (°C) [5] Total mass in reaction (g)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter6: Thermochemistry

Section: Chapter Questions

Problem 68E: In a coffee-cup calorimeter, 1.60 g NH4NO3 is mixed with 75.0 g water at an initial temperature of...

See similar textbooks

Similar questions

Magnesium sulfate is often used in first-aid hot packs, giving off heat when dissolved in water. A coffee-cup calorimeter at 25C contains 15.0 mL of water at 25C. A 2.00-g sample of MgSO4 is dissolved in the water and 1.51 kJ of heat are evolved. (You can make the following assumptions about the solution: volume=15.0 mL, density=1.00 g/mL, specific heat=4.18J/gC.) (a) Write a balanced equation for the solution process. (b) Is the process exothermic? (c) What is qH2O? (d) What is the final temperature of the solution? (e) What are the initial and final temperatures in F?
When one mol of KOH is neutralized by sulfuric acid, q=56 kJ. (This is called the heat of neutralization.) At 23.7C, 25.0 mL of 0.475 M H2SO4 is neutralized by 0.613 M KOH in a coffee-cup calorimeter. Assume that the specific heat of all solutions is 4.18J/gC, that the density of all solutions is 1.00 g/mL, and that volumes are additive. (a) How many mL of KOH is required to neutralize H2SO4? (b) What is the final temperature of the solution?
In a coffee-cup calorimeter, 1.60 g NH4NO3 is mixed with 75.0 g water at an initial temperature of 25.00C. After dissolution of the salt, the final temperature of the calorimeter contents is 23.34C. Assuming the solution has a heat capacity of 4.18 J/C g and assuming no heat loss to the calorimeter, calculate the enthalpy change for the dissolution of NH4NO3 in units of kJ/mol.
Would the amount of heat absorbed by the dissolution in Example 5.6 appear greater, lesser, or remain the same if the heat capacity of the calorimeter were taken into account? Explain your answer.
When 50.0 g of 0.200 M NaCl(aq) at 24.1 C is added to 100.0 g of 0.100 M AgNO3(aq) at 24.1 C in a calorimeter, the temperature increases to 25.2 C as AgCl(s) forms. Assuming the specific heat of the solution and products is 4.20 J/g C, calculate the approximate amount of heat in joules produced.
In a coffee-cup calorimeter, 100.0 mL of 1.0 M NaOH and 100.0 mL of 1.0 M HCI are mixed. Both solutions were originally at 24.6C. After the reaction, the final temperature is 31.3C. Assuming that all the solutions have a density of 1.0 g/cm3 and a specific heat capacity of 4.18 J/Cg, calculate the enthalpy change for the neutralization of HCl by NaOH. Assume that no heat is lost to the surroundings or to the calorimeter.
In 2010, 3.30109 gallons of gasoline were consumed in the United States. The following assumptions can be made: â€¢ Gasoline is mainly n-octane, C8H18(d=0.7028g/mL). â€¢ Burning one mole of n-octane in oxygen releases 5564.2 kJ of heat. â€¢ The heat capacity C of the surface region of the earth is 2.61023 J/K. What is the increase in temperature of the surface region of the earth due to gasoline consumption in the United States?
9.102 A runner generates 418 kJ of energy per kilometer from the cellular oxidation of food. The runner's body must dissipate this heat or the body will overheat. Suppose that sweat evaporation is the only important cooling mechanism. If you estimate the enthalpy of evaporation of water as 44 kJ/mol and assume that sweat can he treated as water, describe how you would estimate the volume of sweat that would have to be evaporated if the runner runs a 10-km race.
9.29 In which case is heat added to the system: (a) E=43J , w=40J ; or (b) E=31J , w=34J ?
The distance between downtown San Francisco and downtown Oakland is 9 miles. However, a car driving between the two points travels 12.3miles. Of these distances, which one is analogous to a state function? Why?
Dissolving 6.00 g CaCl2 in 300 mL of water causes the temperature of the solution to increase by 3.43 C. Assume that the specific heat of the solution is 4.18 J/g K and its mass is 306 g. (a) Calculate the enthalpy change when the CaCl2 dissolves. Is the process exothermic or endothermic? (b) Determine H on a molar basis for CaCl2(s)H2OCa2+(aq)+2Cl(aq)
In the 1880s, Frederick Trouton noted that the enthalpy of vaporization of 1 mol pure liquid is approximately 88 times the boiling point, Tb, of the liquid on the Kelvin scale. This relationship is called Troutons rule and is represented by the thermochemical equation liquid gas H = 88 Tb, joules Combined with an empirical formula from chemical analysis, Troutons rule can be used to find the molecular formula of a compound, as illustrated here. A compound that contains only carbon and hydrogen is 85.6% C and 14.4% H. Its enthalpy of vaporization is 389 J/g, and it boils at a temperature of 322 K. (a) What is the empirical formula of this compound? (b) Use Troutons rule to calculate the approximate enthalpy or vaporization or one mole of the compound. Combine the enthalpy of vaporization per mole with that same quantity per gram to obtain an approximate molar mass of the compound. (c) Use the results of parts (a) and (b) to find the molecular formula of this compound. Remember that the molecular mass must be exactly a whole-number multiple of the empirical formula mass, so considerable rounding may be needed.