Day 3: WATER!

The topic for today: water!! We first began by discussing the objective we had studied for homework.  Each pair of students was assigned a different objective and asked to explain it on the whiteboard by a drawing a picture...the limit was 8 words.  My partner and I explained why coastal regions have a milder climate than inland regions.

Next, we demonstrated the property of water to form a "dome" when you barely overfill a glass or other container. In our experiment, we used a penny.  As you can see, we BARELY overfilled the penny and a dome of water was formed on top of the penny. This is caused by the shape of the water molecules and how they bond together.

 

Finally, we ended the class by discussing a "case study" in a which we compared a runner in Florida to a runner in Arizona.  Once a runner in Florida begins to sweat in order to cool down, water of course forms on the skin. However, since Florida is usually very humid, the water doesn't evaporate very quickly, thus making the runner sweat less. This is worrisome because once the runner becomes hot, there is no way for him to become cool unless he comes indoors or is able to directly pour water onto himself.  In contrast, a runner who sweats in Arizona will be able to immediately feel relief, because the dry heat in Arizona would evaporate the water very quickly, causing the runner to sweat more and thus feel cooler faster. The only thing that the runner needs to worry about is replenishing that water.

Chem Review!!

     As a stepping stone into our unit on BioChemistry, today we reviewed some basic chemistry from last year. To do this we worked on some sheets with problems on molecular structures, Lewis Structures, ionic bonding, and covalent bonding.  For homework, we had studied objectives related to chemistry, and while we were working on our review sheets, we were orally quizzed individually. We choose a random card from a stack and had to answer the question on the card. My question asked how my group controlled our experiment in the the previous milk and food-coloring lab. Overall, the day was very helpful for review and to bring back all those old topics from last year!!

HonBio Day 1

In our first class, we separated into groups of two to conduct experiments with milk, food coloring, and dish soap. Our goal? To understand why the milk swirled around so quickly once a drop of dish soap was added to a pan of milk with drops of food coloring on top.

For part 1 of our experiment, we decided to recreate the video originally shown to us. However, we also repeated the same procedure side-by-side, but using water instead of milk.  Our hypothesis was that the reaction was caused by the bonding of the nonpolar characteristics in the soap and the lipids in the milk.  Thus, if the water did not have the same reaction, our hypothesis would be proved.

Here are the before and after photos from this part of our experiment. We used three drops of yellow food coloring and three drops of blue food coloring in each petri dish.

BEFORE

AFTER

As you can see, the milk and water had the exact same results that we hypothesized.  However, to ensure our accuracy, we tested this 2 more times, each time obtaining the same results.

The final part of our experiment was to test this reaction with Whole Milk instead of 2% milk. We predicted that since Whole Milk has more fats than 2% milk, it would react more with the dish soap. Here are the before and after photos from this part of the experiment:

 BEFORE

AFTER

As shown by the pictures, the reaction was stronger. Though, since the difference in the amount of fat between the two milks is small, the difference was only minimal.

Finally, the whole class came together and created this visual representation of everything we worked with and discovered:

Looking forward to Honors Bio Class 2!!!!!