Wednesday, February 23, 2011

Everything Being Equal Makes for Good Chemistry


Balancing... One Step At A Time

Being able to balance chemical equations is a very important skill for students of chemistry, making this one of our most popular chemistry tutorials. All chemical calculations require you to work with a balanced equation. Here we will show you a simple, easy way to balance all chemical equations you will meet at introductory level chemistry courses.


A chemical equation is balanced when the number of atoms of each type on each side of the equation is the same. Which means if you have 12 hydrogens on the left hand side of the equation, you must have 12 hydrogens on the right hand side, if there are 4 oxygens on the left, there must 4 oxygens on the right, and so on. This is because of the law of conservation of mass - you can't make or destroy atoms during a chemical reaction. But you can't just add atoms at random to each side, you have to work with the molecules of the reactants.

The key to balancing chemical equations is to apply the rules below.
If you already know the rules, then try these worked examples for revision practice.


Balancing chemical equations isn't difficult, once you know the way to do it. Start by finding out how many atoms of each type are on each side of the equation. Some teachers recommend making a little table listing the numbers of each atom for the left hand side and for the right hand side.Example 1


Unbalanced Equation:- C3H8 + O2 ---> H2O + CO2

There are three carbons on the left, but only one on the right.
There are eight hydrogens on the left but only two on the right.
There are two oxygens on the left but three on the right.


Next, look for an element which is in only one chemical on the left and in only one on the right of the equation. (But it is usually a good idea to leave hydrogen and oxygen until you've done the others first.)

To balance that element, multiply the chemical species on the side which doesn't have enough atoms of that type by the number required to bring it up to the same as the other side. The number is called the coefficient.
BUT
If you have to multiply by, say, 2 1/2, do so, THEN multiply EVERYTHING on each side of the equation by two to get rid of the half.
We don't like having halves in equations, as you can't get half a molecule.

Now look for the next element or species that is not balanced and do the same thing.

Repeat until you are forced to balance the hydrogen and oxygens.

Thanks to The Wright Stuff and Sky-Web, http://www.sky-web.net/science/balancing_chemical_equations.htm

Sunday, February 13, 2011

For Your Amusement

FIZIKS IZ FUN

( Much of this material is from The Annenberg Foundation with great appreciation.
They have SUPER stuff.. support them by visiting and learning more about them.
http://learner.org/ and http://www.learner.org/about/legal_policy.html )

Americans are wild about amusement parks. Each day, we flock by the millions to the nearest park, paying a sizable hunk of money to wait in long lines for a short 60-second ride on our favorite roller coaster. The thought prompts one to consider what is it about a roller coaster ride that provides such widespread excitement among so many of us and such dreadful fear in the rest? Is our excitement about coasters due to their high speeds?

Absolutely not! In fact, it would be foolish to spend so much time and money to ride a selection of roller coasters if it were for reasons of speed. It is more than likely that most of us sustain higher speeds on our ride along the interstate highway on the way to the amusement park than we do once we enter the park. The thrill of roller coasters is not due to their speed, but rather due to their accelerations and to the feelings of weightlessness and weightiness that they Roller coasters thrill us because of their ability to accelerate us downward one moment and upwards the next; leftwards one moment and rightwards the next. Roller coasters are about acceleration; that's what makes them thrilling. The centripetal acceleration experienced by riders within the circular-shaped sections of a roller coaster track. These sections include the clothoid loops , the sharp 180-degree banked turns, and the small dips and hills found along otherwise straight sections of the track.produce.

The Clothoid Loop is is the STAR PERFORMER at the amusement park! It is truly out of this world.






You've bought your ticket and boarded the roller coaster. Now you're barreling down the track at 60 miles per hour, taking hairpin turns and completing death-defying loops. Your heart is in your throat and your stomach is somewhere near your shoes. The only thing separating you from total disaster is a safety harness...but are you really in danger?


The designers of the roller coaster carefully crafted this thrilling ride to be just that, but you're actually in less danger than you think. You face a greater threat of injury playing sports or riding a bike than you do on a park ride. Amusement park rides use physics laws to simulate danger, while the rides themselves are typically very safe.

How do physics laws affect amusement park ride design? In this exhibit, you'll have a chance to find out by designing your own roller coaster. Plan it carefully--it has to pass a safety inspection.You can also experiment with bumper car collisions.

Check the physics glossary to find out more about the terms used in this exhibit. Just click on

Ready to roll? Go on to the first ride: The Roller Coaster.

Or your can go
to the Start page...... Zoom

You could of course start by designing your own Roller Coaster,,,,




At any time you can change rides...

Carousels are not considered "thrill machines" by any stretch of the imagination. Still, carousels are as reliant on the laws of motion as their more exciting cousins, the roller coasters. It's theoretically possible that, allowed to spin out of control, a carousel could gain enough speed so that the riders would be thrown off. Thankfully, runaway carousels are not the least bit common.

Newton's third law of motion comes into play on the bumper cars. This law, the law of interaction, says that if one body exerts a force on a second body, the second body exerts a force equal in magnitude and opposite in direction on the first body. It's the law of action-reaction, and it helps to explain why you feel a jolt when you collide with another bumper car.

Galileo first introduced the concept of free fall. His classic experiments led to the finding that all objects free fall at the same rate, regardless of their mass. According to legend, Galileo dropped balls of different mass from the Leaning Tower of Pisa to help support his ideas.


Pendulum rides are a little like the swing sets you might remember from your childhood. Swings give you a feeling of flying in a controlled manner. You pump your legs to provide enough force to increase the height of the swing's arc, and enjoy the increased velocity of the downward swing. When you stop pumping, the swing gradually slows and then stops.

Ride Safety depends on getting the "math" right don't ya know.

Going on amusement park rides is one of the safest forms of recreation. According to the International Association of Amusement Park Attractions, you are more likely to be injured when you play sports, ride a horse, or even ride a bicycle. Statistics show the occurrence of death to be approximately one in 250 million riders.

Get data on Roller Coasters from all over ....

You can check their claims ...

"Fastest !! " (? really ?)
"Greatest Acceleration !!" ( can you prove it?)
"Highest Speed !!" (is it possible?)


...simply do the Math ! Use the right equations and you can calculate if you are really getting your money's worth




Many of the best amusements are exciting because you can "sense" the feeling of flight. You can find out more about the Fundamentals of Flight here in .....

FLIGHT , THE BASICS from the Smithsonian.


Flight, A Very Natural Occurrence
Gliding Flight
True Flight
Principles of Flight
What is Aeronautics?
How Fluids Move
How Liquids Behave
How Air Moves - Aerodynamics
Measurement
Properties
How Air Moves Over Objects
The National Business Aviation Association.



So... What do you think? ... AMUSING?

Think about velocity, momentum, impulse, force, speed, acceleration, Newton, Galileo ... algebra, mathematics, geometry ....

The next time you get on a new amusement ride, do you hope that the designers paid attention in class?

Thursday, February 3, 2011

A Model Concept

Making Models for Understanding.

There are many methods of reaching understanding - all begin with the use of one, two, three, four or all five of our senses.

What we do with the input, the information, the raw "data" we gather, ... is the

How we process for understanding.

Skill + Knowledge = Understanding
The precision of SKILL we use to process the information or KNOWLEDGE,
becomes our UNDERSTANDING


There are so many ways , so many paths to understanding and discovery..

....inductive reasoning, deductive reasoning, (favorites of a famous investigator )...logical organization, scientific methodology etc.

One very powerful way is; similarity comparison, metaphor or analogy.
I am proud to share one from
one of my students.



For example;

The Periodic table can appear daunting , complex and even a bit scary...



Here is a way one of our own "Sherlock Holmes" clues us into an understanding of the periodic table.


Sherlock;

If anyone needs help with the periodic table? If so read on. ( think about what we're studying in Mr. Nevins class 4.3 especially)

Helium, Neon,Argon, Krypton, Xenon, Radon, and Ununoctium, they're the plantation owners (Noble gases) and self-sufficient.


-test your knowledge of the Noble elements -




Independent small farmers (Metals) aren't self-sufficient and need help to be whole.

Nonmetals are immigrants that aren't considered high in society, but are still regarded.

Slaves (transitional - the are really odd. find out why!) aren't considered fully human (closer to animals), so they don't fit in with anyone.


Sherlock/yellow

P.S. Hope this helps and I couldn't figure out who the Lanthanide and Actinide Series could be ???

...discovery is fascinating...


And now another investigator continues with metaphor and analogy... how cool is this ?!?

**ALSO...

...and Like how the enslaved natives and the Africans weren't very different from one another (except how the natives escaped slavery and the Africans did not)Alkali metals and Alkali earth metals aren't very different from one another as well...

The main difference between the two is their atomic configuration (an alkali earth metal has two electrons in it's outer-most energy level- valence , and alkali metals only have a single electron, this means that they are both highly reactive).

Alkali metals (lithium, sodium, potassium, rubidium, cesium, and francium) make up Group 1 on the Periodic Table.



Alkali earth metals (beryllium, magnesium, calcium,strontium, barium, radium)make up Group 2 on the Periodic Table.


****To always remember alkali metals & alkali earth metals' places on the Periodic Table is that how the Native Americans were first to escape enslavement then the Africans (alkali metals [the "Natives"] are first to the very left of the Periodic table, then the alkali earth metals [the "Africans"]come right after them...***

-Kaitlyn, Yellow

the Analysis continues: