Experiment 16: Heat generation during reaction

Objective

• To measure the change in temperature during chemical reactions and to conclude whether the reaction is exothermic or endothermic

Materials required:

• Dil Sodium hydroxide solution
• Dil hydrochloric acid,
• ammonium chloride (solid)
• barium hydroxide (solid)
• four test tubes
• thermometer (–10 ºC to 110 ºC)

Procedure:

• Mark all the four clean test tubes as 1, 2, 3, and 4.
• Take 5 mL of sodium hydroxide solution in test tube no. 1; 5 mL of hydrochloric acid in test tube no. 2
• Add 1g of barium hydroxide with 5ml of water in # 3, and 1g of ammonium chloride with 5ml of water in #4
• Record temperatures of each TT
• Pour the contents of TT no. 1 in TT no. 2 and record the final temperature reading of the thermometer
• Pour the contents of TT no. 3 in TT no. 4. and record the final temperature readings of the thermometer

 

Findings:

Conclusions:

• The reaction between sodium hydroxide solution and hydrochloride acid is exothermic
• Reaction between barium hydroxide solution and ammonium chloride is endothermic.

Theory:

• The chemical reactions in which energy is absorbed are called endothermic reactions and those in which energy is released are known as exothermic reactions.