To study the exothermic and endothermic reactions

Science Experiment 5.3PEKA Evaluation 2009-

201015 September 2009

Azneezal Ar-Rashid

Smk Sri Aman95007 Sri Aman,

Sarawak

Aim

• To study the exothermic reaction and endothermic reaction

Problem statement

• How can exothermic reaction and endothermic reaction can be identified

Hypothesis

• Exothermic reaction releases heat, while endothermic reaction absorbs heat

Variable

• Constant :– Initial temperature

• Manipulated :– Types of material

• Sodium Hydroxide Crystals• Ammonium Chloride Crystals• Sodium Chloride Crystals

• Responding :– Final temperature

Materials

• 1 spatula of – Sodium Hydorixe crystals (Beaker A)

• 1 spatula of – Ammonium Chloride crystals (Beaker B)

• 1 spatula of – Sodium Chloride crystals (Beaker C)

• Distilled water

Apparatus

• 3 Beakers

• 1 thermometer

• 3 spatulas

Procedure/Method

• About 20 ml of distilled water is poured into a beaker

• The initial temperature of the distilled water is recorded

• A spatula of Sodium Hydoxide Crystals is added in the beaker

• The mixture is stirred• The final temperature is recorded• The experiment is repeated using Ammonium

Chloride Crystals and Sodium Chloride Crystals

Results/Observation Table

Material Initial temperature

Final temperature

Change in temperature

Outer wall of beaker

Sodium Hydroxide Crystals +

Distilled Water

___ C ___ C ___ C Hot/Cold/

No Reaction

Ammonium Chloride

Crystals + Distilled Water

___ C ___ C ___ C Hot/Cold/

No Reaction

Sodium Chloride

Crystals + Distilled Water

___ C ___ C ___ C Hot/Cold/

No Reaction

Conclusion

• Exothermic reaction causing the temperature of the solution to increase/decrease

• Endothermic reaction causing the temperature of the solution to increase/decrease

• The hypothesis can/cannot be accpeted

• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction) • Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)• Sodium hydroxide (exothermic reaction)

• Ammonium chloride (endothermic reaction)

• Ammonium chloride (endothermic reaction)

• Ammonium chloride (endothermic reaction)

• Ammonium chloride (endothermic reaction)