5 g of molten NaCl is at melting temp. The salt is added to 25 mL...
5 g of molten NaCl is at melting temp. The salt is added to 25 mL of water at 25 C in a coffee cup calorimeter. The salt becomes solid and the temp of water increases to 47.9C.
a.) calculate amount of heat transferred in Joules
b.) is the freezing of salt endothermic or exothermic?
c.) calculate the moles enthalpy of fusion for NaCl in kJ/mol
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5 g of molten NaCl is at melting temp. The salt is added to 25
mL...
1. A coffee cup calorimeter was used for the neutralization reaction of 100 mL of 1.00...
1. A coffee cup calorimeter was used for the neutralization reaction of 100 mL of 1.00 M hydrochloric acid with 100 mL of 1.20 M sodium hydroxide. The initial temperature was 22.88 °C and the final temperature was 29.39 °C. Calculate the calorimeter constant for the reaction. HCl (aq) + NaOH (aq) NaCl (aq) + H2O (∆H°rxn = -58.3 kJ/mol) 2. The same calorimeter was used for the dissolution of 8.86 g sample of lithium chloride in 100.0 mL of...
A 7.41 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 15.00...
A 7.41 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 15.00 g water in a coffee cup calorimeter. Before placing the sample in the water, the temperature of the salt and water is 23.72 degrees celsius. After the salt has completely dissolved, the temperature of the solution is 28.54 degrees celsius. A) Was the dissolution process endothermic or exothermic? B) What is the heat for the dissolution reaction?
Please show work! 3. The data graphed at the right was obtained when 4.00 g of a salt (molar mass = 80.0 g/mol) was...
Please show work!
3. The data graphed at the right was obtained when 4.00 g of a salt (molar mass = 80.0 g/mol) was dissolved in 100 mL of water in a Styrofoam cup calorimeter. a. Is the process exothermic or endothermic? b. Calculate AT. c. What is the AHrxn for the system in kJ/mol? Show your work. (Assume the Ccup is negligible)
hen 170. mL of 0.209 M NaCl(aq) and 170. mL of 0.209 M AgNO3(aq), both at...
hen 170. mL of 0.209 M NaCl(aq) and 170. mL of 0.209 M AgNO3(aq), both at 21.6°C, are mixed in a coffee cup calorimeter, the temperature of the mixture increases to 24.2°C as solid AgCl forms. NaCl(aq) + AgNO3(aq) → AgCl(s) + NaNO3(aq) This precipitation reaction produces 3.68 ✕ 103 J of heat, assuming no heat is absorbed by the calorimeter, no heat is exchanged between the calorimeter and its surroundings, and that the specific heat and density of the...
An ice cube of mass 9.0g is added to a cup of coffee, whose temperature is 90.0 °C and which contains 120.0 g of li...
An ice cube of mass 9.0g is added to a cup of coffee, whose temperature is 90.0 °C and which contains 120.0 g of liquid. Assume the specific heat capacity of the coffee is the same as that of water. The heat of fusion of ice (the heat associated with ice melting) is 6.0kJ/mol. Find the temperature of the coffee after the ice melts. Use the equation given in the lab manual on page 86. Ignore the + (CC) (AT)...
Pre-lab Study Questions 1. Calculate the enthalpy of reaction DHrxno for each of the following reactions using the t...
Pre-lab Study Questions 1. Calculate the enthalpy of reaction DHrxno for each of the following reactions using the tabulated standard enthalpy of formation DHfo. (Show calculation) a. H2O(g) ® H2O(l) b. CaCO3(s) ® CaO(s) + CO2(g) c. CH4(g) + 2 O2(g) ® CO2(g) + 2 H2O(g) 2. Consider the following reaction and the given standard enthalpy of formation DHfo. NH4NO3(s) ® NH4+(aq) + NO3-(aq) DHfo (kJ/mol) -365.6 -132.0 -205.0 a. Calculate the enthalpy of reaction DHrxno for the above reaction...
32. The following hypothetical circumstance takes place in a coffee-cup calorimeter. Dissolving 3 moles of a...
32. The following hypothetical circumstance takes place in a coffee-cup calorimeter. Dissolving 3 moles of a salt in water results in a 100 gram solution that increases in temperature by 3°C. What is the enthalpy of this reaction? The specific heat capacity of water is 4.184 J/g* °C A. 1.255 kJ/mol B. -225.9 kJ/mol C. -0.4184 k/mol D. -0.2259 kJ/mo
Q 1. a. A process in which heat is given off is said to be _____________________...
Q 1. a. A process in which heat is given off is said to be _____________________ (endothermic or exothermic) b. DH is negative for an ___________________ (endothermic or exothermic) reaction c. If a reaction is carried out in solution, and the solution gets cooler as the reaction occurrs, the reaction must be ___________________ (endothermic or exothermic) d. A hot penny is dropped in water, and 25.2 J is tranferred from the penny to the water. q for the water =...
1. A volume of water was heated to 83.90 °C and immediately added to 48.11 mL...
1. A volume of water was heated to 83.90 °C and immediately added to 48.11 mL of water at 23.98 °C contained within a coffee cup calorimeter. The final temperature of the mixture was 40.86 °C. The final volume of water inside the calorimeter was 90.45 mL. Assuming that them heat capacity of the solution is 4.18 J/g/°C, calculate the following: a. The volume of hot water added ml b. The mass of hot water (dwater = 1.00 g/mL) c....
12:47 1 Exit Question 1 0.5 pts When 34.8 g of sodium chloride is dissolved in...
12:47 1 Exit Question 1 0.5 pts When 34.8 g of sodium chloride is dissolved in water, 2.31 kJ of energy is absorbed. Is the enthalpy of dissolution of NaCl exothermic or endothermic? Endothermic Exothermic Question 2 0.5 pts What is the balanced thermochemical equation for the combustion of two moles of gaseous acetylene, C2H2, with oxygen to produce carbon dioxide and water vapor at 24.59°C given that 2512 kJ of heat is released at a constant pressure of 1.14...
Please show work!
3. The data graphed at the right was obtained when 4.00 g of a salt (molar mass = 80.0 g/mol) was dissolved in 100 mL of water in a Styrofoam cup calorimeter. a. Is the process exothermic or endothermic? b. Calculate AT. c. What is the AHrxn for the system in kJ/mol? Show your work. (Assume the Ccup is negligible)
An ice cube of mass 9.0g is added to a cup of coffee, whose temperature is 90.0 °C and which contains 120.0 g of liquid. Assume the specific heat capacity of the coffee is the same as that of water. The heat of fusion of ice (the heat associated with ice melting) is 6.0kJ/mol. Find the temperature of the coffee after the ice melts. Use the equation given in the lab manual on page 86. Ignore the + (CC) (AT)...
32. The following hypothetical circumstance takes place in a coffee-cup calorimeter. Dissolving 3 moles of a salt in water results in a 100 gram solution that increases in temperature by 3°C. What is the enthalpy of this reaction? The specific heat capacity of water is 4.184 J/g* °C A. 1.255 kJ/mol B. -225.9 kJ/mol C. -0.4184 k/mol D. -0.2259 kJ/mo
1. A volume of water was heated to 83.90 °C and immediately added to 48.11 mL of water at 23.98 °C contained within a coffee cup calorimeter. The final temperature of the mixture was 40.86 °C. The final volume of water inside the calorimeter was 90.45 mL. Assuming that them heat capacity of the solution is 4.18 J/g/°C, calculate the following: a. The volume of hot water added ml b. The mass of hot water (dwater = 1.00 g/mL) c....
12:47 1 Exit Question 1 0.5 pts When 34.8 g of sodium chloride is dissolved in water, 2.31 kJ of energy is absorbed. Is the enthalpy of dissolution of NaCl exothermic or endothermic? Endothermic Exothermic Question 2 0.5 pts What is the balanced thermochemical equation for the combustion of two moles of gaseous acetylene, C2H2, with oxygen to produce carbon dioxide and water vapor at 24.59°C given that 2512 kJ of heat is released at a constant pressure of 1.14...
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