Gas Laws Save Lives

In the modern world, a car without an airbag is unheard of. The goal of the airbag is to stop the momentum of the passenger, with as little damage to the person as possible. This life saving technology is a necessity, and believe it or not, it is based off of the Gas Laws of Chemistry.

The image above depicts what happens when an airbag is set off. http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/airbag1.htm

First off, an airbag works by inflating (duh!). More importantly, is how it inflates. The bag is made of a thin nylon attached to a sensor. When a collision force of 10-15 miles per hour or more occurs, a mechanical switch is flipped, and the sensor receives a message to inflate. The airbag’s inflation system then reacts sodium azide (NaN3) with potassium nitrate (KNO3) to produce nitrogen gas, which then fills the airbag. Quickly afterward, the gas diffuses, so that the passenger can get out of the car.

This whole process is based off of the Gas Laws. When the sensor turns on the electrical circuit and releases NaN3, the volume increases because the amount of substance increases. Previously, there was no gas in the airbag, so when gas is pumped in, it inflates. This is supported by Avogadro’s law, n1/V1=n2/V2. Essentially, this law states that an increase in the moles of substance present increases the volume, therefore effectively expanding the airbag. Who knew we had Chemistry to thank for such a useful device?!

Three Questions May 9th

1. What tasks have you completed recently?

Recently, I have completed tons of homework assignments, including reaction practice problems for chemistry, coloring packets for anatomy, and nightly reading for English. I have also worked on my Spanish Portfolio Project, which is due Friday. 

2. What have you learned recently?

Recently, I have learned the difference between reaction types and how to predict products in Chemistry, along with the gas laws; in Anatomy I have learned about the differences in blood types and the mechanisms of the cardiovascular system. In addition, in government, I have learned about multiple interest groups and their lobbying effort; in English, how to use parallelism correctly.

3. What are you planning on doing next? 

Next, I plan on cramming for finals, particularly chemistry. In terms of out of school activities, I plan on trying to piece back together my house, as it was recently flooded by our upstairs neighbor. Yay for cleaning up plaster covered floors!!!