Analía Bellizzi – Chemistry Classes

Ronald Reagan High School

AS Enthalpy of Neutralization

Enthalpy of Neutralization Lab

Materials:  
  • HCl 2M (around 100 cm3)
  • NaOH 2M (around 100 cm3)
  • 2 beakers labeled “acid’ and “base”
  • 2 50 cm3 graduated cylinders labeled “acid’ and “base”
  • Thermometer
  • Styrofoam cup and 400 cm3 beaker to hold it up
  • Paper towels
SETUP: Procedure:
  1. Measure exactly 50 cm3 of the acid into the Styrofoam cup and place the thermometer until the temperature stabilize. RECORD                      ºC. Wipe the thermometer using paper towels.
  2. Calculate the number of moles of acid present in the measured solution
  3. Measure 50 cm3 of the base in the graduated cylinder and measure the temperature. 
  4. RECORD                       ºC
  5. Calculate the number of moles of base present in the measured solution   
  6. Pour the base into the Styrofoam cup containing the acid and swirl the resultant solution using the thermometer. Record the maximum temperature                      ºC
  7. Write the equation of neutralization between Hydrochloric acid and Sodium Hydroxide.
  8. Calculate the number of moles of water formed in the total solution   
  9. Assuming the density of the solution is 1g cm-3, how many grams of solution are present in the Styrofoam cup?  
  10. Calculate the Q of the reaction Q = m x c x Δt, where m is the mass of solution, is the specific heat of water (4.18 J g-1 ºC-1)
  11. Calculate how much energy will be released when 1 mol of water would form (ΔH)
  12. Repeat the experiment using 25 cm3 of each solution instead and perform all the calculations again.
  13. What can you conclude from your observations?