Objective: Find the standard molar enthalpy of combustion for magnesium.
Manipulated Variables- volume of HCl, length of magnesium strip, mass of magnesium oxide,
Controlled Variable- type of calorimeter (Styrofoam cup)
Responding Variable- change in temperature
1. Cut out 3 pieces of magnesium strips each with lengths of maximum 5 centimeters. 2. Measure and record the lengths of the magnesium. 3. Scrub the magnesium strips with steel wool to clean out impurities. 4. Pour out approximately 310 mL of hydrochloric acid from the stock container. 5. Use a 50mL or 100mL graduated cylinder to measure approximately 50mL of hydrochloric acid. 6. Record the volume of hydrochloric acid. 7.…show more content…
Repetitive washing did not clean the bottom fully. | 2 | Same as above | Same as aboveFinal temperature remained 33.3°C for 90s, then decreased to 33.5°C | Same as above | 3 | Same as above | Same as aboveFinal temperature remained 32.6°C for 90s, then decreased to 32.5°C | Same as above |