Science- Week 6

Topic: Acids and Bases

 

This weeks memory sentence explained the differences between acids and bases. To help visualize this, we discussed the differences between a lemon and a bar of soap. Then it was time to experiment with some household items to see if they were acidic or basic! 

First, we tested orange juice, vinegar, and laundry detergent. The children guessed that the OJ and vinegar were acids, and that the laundry detergent was a base. We tested it by placing drops of each on blue and red litmus paper. The children guessed all three correctly.

Next, we tested 7-Up, lemon juice, and Windex. The children guessed that the soda and lemon juice were acids, and that the Windex was a base. This time we tested it by adding red cabbage juice to each. If the item turned a reddish-pink, it was an acid. If it turned yellowish-green, it was a base. It was really neat watching them change colors! The children made the correct guesses again. 

Last, we retested everything to see where it landed on the pH scale. I had a special solution to add to each item, and we watched the colors change again. The children did a great job finding the correct spot for each on the pH scale.

Science- Week 5

Topic: Chemical Reactions

This week we experimented with five chemical reactions. Combustion, Synthesis, Decomposition, Single Displacement, and Double Displacement. To help the the children remember this, I taught them an easy mnemonic phrase. Come See Dad Sing and Dance. To remember the second word in the last two, just think that if Dad was to dance, he might displace (like dislocate) a bone. ;) 

I then demonstrated the activities suggested in our CCM book for week 5. The kids enjoyed blowing up a balloon with vinegar and baking soda. :) Ask them about our decomposition experiment, where I added a slice of potato to hydrogen peroxide. Hydrogen Peroxide is H2O2. When you add a raw potato, it attracts one of the oxygen molecules (which we could see by the bubbles forming on the potato) causing the peroxide to turn into H2O- water! 

Here's a neat experiment you can try at home if you have 6% hydrogen peroxide (the kind you find at the store is only 3%):

http://www.sciencebob.com/experiments/toothpaste.php