Life is a Gas!

Warm up

Book HW out for stamp please!

HW questions?

Presentation Demonstration

HW: Complete the KWL for Th/F

1. Come up with THREE questions2. Fill in the K and W sections3. Do a brief google search - fill in the L and the

follow up questions4. We’ll meet one on one (Th/F) to hone in your

final choice

As you watch the demo

This is an exemplar student presentation from last year...Jot down your thoughts on -• What do you notice about the presentation

slides?• What would you change? Keep the same?• What do you notice about the presentation

style?

Why is baking soda used for quick breads?By __________________

Yum!

Image from https://www.simplyrecipes.com/recipes/banana_bread/ 3/20/17

Typical recipe from Simply Recipes

The magic ingredient!

Chemical formula:

NaHCO3

This is an ionic compound made up of a sodium ion and a bicarbonate ion

Baking SodaFound in nature, it is an important component in many biological systems because it can act as a buffer (from Science activities magazine)

What is a buffer?!?!

A substance that is capable of neutralizing both acids

and bases (from Merriam-Webster)

Other facts: It is a white powder, with a crystalline structure. Can be used for all sorts of household tasks!

Image from http://www.ducksters.com/science/acids_and_bases.php on 3/18/17

The many uses of baking soda

https://food-hacks.wonderhowto.com/how-to/safely-put-out-grease-fire-and-prevent-them-altogether-0152942/

https://www.rentokil.com/blog/diy-cockroach-control/#.WqkpNpPwbGI

https://www.healthtap.com/topics/heartburn-indigestion-male-men-nipple-pain

http://www.expressflooring.com/blog/cleaning-shower-grout-how-to-clean-shower-tile-grout-homemade-tips/

ZOOM in on baking

Decomposition of baking soda

NaHCO3 (s) → CO2 (g) + H2O (g) + Na2CO3 (s)

This happens above 150oF

This is a decomposition reaction!

Image: From https://memegenerator.net/instance/48799275/forgetful-dory-heres-bubbles-oooooh-look-bubbles

This is what we are going for! BUBBLES!

Trapping the bubblesThe batter traps the bubbles while cooking so the quick bread is less dense.

At high altitude if the batter is TOO THIN the bubbles can escape.

Add more flour to strengthen the structure of the bread

Also, decreasing the amount of baking soda from ~1 tbs to ⅞ tbs can help!

From https://www.kingarthurflour.com/learn/high-altitude-baking.html

Works cited

"Baking Soda Chemistry: The Basic Principles." Science Activities, vol. 31, no. 4, Winter95, p. 28. EBSCOhost, search.ebscohost.com/login.aspx?direct=true&db=sch&AN=9504211263&site=ehost-live.

Hughes, Lynn. "Keep Your Baking Routine Simple." Countryside & Small Stock Journal, vol. 96, no. 3, May/Jun2012, p. 40. EBSCOhost, search.ebscohost.com/login.aspx?direct=true&db=sch&AN=74745170&site=ehost-live.

https://www.simplyrecipes.com/the_difference_between_baking_soda_and_baking_powder/ found on 3/13/2018

https://www.kingarthurflour.com/learn/high-altitude-baking.html found on 3/13/2018

Kelvin and absolute zero

• Kelvin scale: 0 K is the lowest possible

temperature – absolute zero

• There are no negative temperatures as there

are with the Fahrenheit and Celsius scales

• Converting to Kelvin is EASY!!

– Take your Celsius temp and add 273 to it!

– Example: Convert 23.0oC to K

• Answer: 23.0oC + 273 = 296 K

• To convert from K to Celsius, simply subtract 273 from

the K temperature

– Example: Convert 200 K to Celsius

POGIL “Life is a Gas!”

• Go to website. Search “Gas Properties” simulation. Choose “Gas Properties”

• DL• Edit security on your computer if you need

(under settings).• DL Java – (JDK) and install• Return to DL list, Run PhET program.• Enjoy!

If Life is a Gas does not work

• See next two slides for tips on “Gas Variables” POGIL

NOTES and EDITs for “Gas Variables” POGIL

#4: The IV can be found in ( ) by the title of each experiment. Look to the changing variables for DV.#11. Instead of writing an algebraic equation, use an arrow to show what happens to internal pressure (P) as number of particles (n) increases. Use an arrow to show what happens to internal pressure (P) as temperature (T) increases.#13 – See tip for #4

NOTES and EDITs for “Gas Variables” POGIL

#20 - Instead of writing an algebraic equation, use

arrows to show the relationship between the

independent and dependent variables in exp C –E

#23 – Read pages 442 – 448. Amontuns’ law is Gay –

Lussac’s Law

#23 – Avogadro’s law relates P and n. Based on the

way the relationships are written for Boyle, Charles

and Gay – Lussac’s, write Avogadro’s law as an

algebraic expression.

#24 - See pages 452 – 454 (Find the IDEAL gas law

rather than the COMBINED gas law)