Peka Science Year 5

Date	:	20-7-2010
Activity Code	:	5 /2 / 2.1 / 1
Theme	:	Investigating Materials
Topic	:	2. Acid and Alkaline
Learning Outcomes	:	4.1.1 Pupils identify acidic, alkaline and neutral substances using litmus paper.
Aim	:	To investigate the relationship between the type of solution and the change of blue and red litmus paper
Apparatus	:	Solution P(mineral water), solution Q (salt water), solution R (vinegar), solution S (panadol solution), solution T (toothpaste) and solution U (lime juice)， blue litmus paper and red litmus paper,beakers and petri dishes
Method	:	1.      Pour small amaunt of solutions given in the petri dish. 2.      Taste all solutions P,Q,R,S,T and U. Record your observation. 3.      Then dip a red litmus paper  in the solution P and observe the colour changed. 4.      Then use blue litmus paper and observe the colour change. 5.      Record your finding in the table below. 6.      Repeat the above activity using solutions Q,R,S,T and U.
Observation	:
Solutions Observations Red litmus paper Blue litmus paper P (Mineral water ) Does not change colour Does not change colour Q (Salt) Does not change colour Does not change colour R (Vinegar) Does not change colour Turn to red S (Panadol Solution) Turn to blue Does not change colour T (Tooth paste) Turn to blue Does not change colour U (Lime juice) Does not change colour Turn to red
Discussion	:
1.      Group the solutions above correctly. Acidic Solution R Solution U Alkaline Solution S Solution T Neutral Solution P Solution Q 2.      Which solution have a same properties as a detergent?        Solution S and T Predict how do the colour of blue  and red litmus paper changed  if we test the lemon juice.             Blue litmus paper will change to red and the red litmus paper does not change its colour. Conclusion   :     Acidic substances change the colour of blue litmus paper to red/ Alkaline substances change the colour of red litmus paper to blue/ Neutral substances do not change the colour of red or blue litmus paper.