Endothermic reactions

Heat absorbing reactions- Cool.
Not all reactions give off heat, light or sound some actually quietly absorb heat from their surroundings and actually cool things down. Let's see one cool chemical reactions that is endothermic, heat absorbing, reaction that we can try in the kitchen.
What you will need.
- Bi-Carb Soda
- Vinegar
- Zip-lock plastic bag
- Thermometer

 
   

Step 1 - pour in one glass of vinegar.

Step 2 - place a teaspoon of Bi-Carb Soda in the plastic bag.
   

A chemical reaction quickly takes place producing a great deal of fizzing and a gas.
Wait for 30 seconds before zip locking the bag as the gas will build up and cause the bag to rupture spilling its contents all over the floor.

Handling the bag you can feel how cold it gets.
   

Extension activity.

Set up an investigation to answer the following question. When mixing Bi-Carb Soda and vinegar , will the temperature drop more when using double strength vinegar than when using single strength vinegar?

Write a hypothesis.
Write a procedure to test the hypothesis above.