When a 2.66-g sample of solid ammonium chloride dissolves in 37.8 g of water in a coffee-cup calorimeter (see above figure) the temperature falls from 21.00 oC to 16.68 oC. Calculate H in kJ/mol NH4Cl for the solution process.

In a coffee cup calorimeter, 50.0 mL of 1.00 M NaOH and 50.0 rnL of 1.00 M HCI are mixed. Both solutions were originally at 24.6 °C. After the reaction, the final temperature is 31.3 °C. Given that the density of NaCl solution is 1.038 g/mL and the specific heat of NaCl solution is 3.87 J/g-°C, calculate the ΔHneut/mole for the reaction of HCl with NaOH. Assume that no heat is lost to the surroundings.

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