One of the richest yet least-known annual displays of “shooting stars” starts off the new year. But this time around, it will be sharing the sky with a brilliant source of natural “light pollution” - the Full Moon! Despite its interference, this display will still be worth watching.
Among the meteor showers to grace our skies each year, that known as the Quadrantids outranks nearly all of them, including the famed Perseids in August. Its peak hourly meteor rate is only matched by that of the Geminids in December. Under clear, dark sky conditions, observers can expect to see 100 or more shooting stars per hour at its peak (compared to about 80 for the Perseids). In 2008, the shower will occur between January 1st and 5th, with maximum activity coming on January 4th. The radiant - that point in the sky from which the meteors appear to stream - lies in the constellation Bootes. And although it doesn’t rise until well after midnight in January, meteors can still be seen shooting from over the northeastern horizon after darkness falls.
Continue reading ‘The Quadrantid Meteor Shower’
Archive for December, 2007
Purpose
Illustrate the variety of odors that are produced from esters.
Materials
- Organic alcohols in dropper bottles (see chart below)
- Organic acids in dropper bottles (see chart below)
- Sulfuric acid, H2SO4 (18 M)
- Sodium carbonate, Na2CO3
- Test tubes
- Test tube holder
- Bunsen burner
- or, the Ester Formation Lab Activity
Purpose
To illustrate expansion of gases under reduced pressure.
Materials
- Shaving cream
- Marshmallow
- Soda water
- Doll’s head
- Vacuum pump with bell jar
The identification of living or non-living things can be greatly simplified by using a tool known as a dichotomous key. The word dichotomous literally means “divided in two parts”. It therefore stands to reason that a dichotomous key divides a set of objects into two subsets based on the presence or absence of a particular character. Each question within the set leads to another set of more specific questions and so on, until the user reaches a conclusion as to the identity of the object. This form of classification is the one used most often by taxonomists because it offers the user a quick and easy way of identifying unknown organisms.
For an organism to survive, it needs to get rid of metabolic waste materials, as well as maintain proper concentrations of various necessary materials. For example, human food consists of carbohydrates, fats, proteins, various salts, and water. As these materials are metabolized, certain waste products are produced, such as carbon dioxide, water, urea and related nitrogenous compounds, salt, and various minerals. If these waste materials remain in the body, they quickly upset the body’s equilibrium (homeostasis), so they must be excreted rapidly and efficiently.
The kidneys are very important organs within the human body because they are essential to maintaining homeostasis. Humans have two bean-shaped kidneys that are found at the back of the abdominal cavity, one found on each side of the spine. Each kidney is approximately the size of a person’s fist. All the blood in the body must pass through the kidneys. The large amount of blood that is passed through the kidneys allows them to do the following: Continue reading ‘Kidney Dialysis Simulation’
Investigate acid-base reactions by creating a volcanic eruption
Published in Science at Home and Lesson Plans.Create your own volcanic eruption and investigate acid-base reactions.
You will need:
- Baking soda
- A “volcano” –a container to hold the reaction
(Note: a fun related art project is to create and paint your own volcano out of Plaster of Paris or paper-maché with a built-in well to hold the reagents.)
Safety Tips:
Provide paper towels to clean up the resulting eruption – it can be a fizzy mess. The lab’s reagents are harmless, but you should take care to avoid contact with your eyes.
Continue reading ‘Investigate acid-base reactions by creating a volcanic eruption’
Purpose
To illustrate a combustion reaction.
Materials
- Rubbing alcohol (70% isopropyl alcohol)
- 19 L plastic water bottle (water cooler jug)
- Meter stick with candle on the end (or barbeque lighter)
- Safety shield
- 50 mL graduated cylinder
Purpose
To illustrate a non-spontaneous and spontaneous reaction.
Materials
- Copper (II) chloride, CuCl2 (1.0 M solution)
- 2 ea. graphite
- Power source (15V max.)
- Volt meter
- Electrical leads (with Alligator Clips)
- 250 mL
- 100 mL graduated cylinder
Continue reading ‘Rechargeable Battery ScholAR Demonstration’
Purpose
To illustrate several principles of batteries by using orange juice to power an electric clock.
Materials
- Magnesium strip or ribbon
- Copper strip
- Orange juice
- Steel wool (not a soap pad)
- Electrical leads (with Alligator Clips)
- Battery powered clock (variety that requires a single 1.5 V AA battery)
- 250 mL
