Seiple,+Savannah

I didn't know that distillation was used to separate elements in crude oil. I also didn't know what hydrocarbons were, and that some of them boiled and condensed at different temperatures. I did know that crude oil was very flammable. However, I still don't know why the hydrocarbons need to be separated.

Savannah, OK, but pretty short (52 words). 4 stars. MW

I read the first few pages of the Harry Potter article. 3 things I already knew were that scientists cannot replicate the instant-traveling effects of Floo Powder in the Potter movies. I also knew that different colored flames could be created, and that a sparkler is similar to a wand in the sense that they both send out sparks. Three things I didn't know were that holding flames can be recreated by using a flashpaper, a form of cellulose nitrate. I also didn't know that it is possible to make invisible and colorchanging ink with items usually found in the average household. I also didn't know that the brilliant green flame created when "Floo Powder" is tossed into a fireplace can be created by sprinkling boric acid powder into a flame.

Savannah,

I'm glad you read the Harry Potter article. It looks like you picked up a few good items! 5 stars. MW

I found this article interesting because I have always wondered how different types of motion detectors worked. I already knew that some motion detectors, such as the safety feature used with garage doors, used a light beam aimed at a photo sensor. I also knew that home security motion detectors using lights, like the one first mentioned in the article, would usually not turn on unless a human being came near it. I didn't know that some motion detectors used sensors to monitor infrared radiation. I guess that explains why inanimate objects usually don't set off motion detectors. I also didn't know that some motion detectors used a method similar to echolocation, which I knew was used by bats, to detect when an object was near

-Savannah Seiple Savannah, Be sure to include 3 things you knew and 3 things you learned- looks like you just have 2 of each. 4 stars. MW