Dalton's Law

Blog Post #4

(May 11, 2016)

Dalton's Law tells us that for a mixture of gases in a container, the total pressure exerted is the sum of the pressures that each gas would exert if alone.

https://i.ytimg.com/vi/RqffPYOoxd8/maxresdefault.jpg

The pressure of a gas is unaffected by the identity of the gas.

Helpful Links:
Gas Laws-Laws of Partial Pressure
Gas Law Problems-Dalton's Law

Avogadro's Law

Blog Post #3

(May 11, 2016)

Avagadro's Law tells us that for gas at constant temperature and pressure, the volume is directly proportional to the number of moles of gas present.

http://thescienceclassroom.org/wp-content/uploads/2013/04/Avogadros-Law.png

As the number of moles of a gas increase, the volume will have to increase in order for the pressure of the system to remain constant.
The volume of one mole of gas at STP is 22.4L.

Helpful Links:ChemTeam-Avogadro's Law
AP Chem: Gas Laws

Charles' Law

Blog Post #2

(May 11, 2016)

Our next law in the gas laws unit consisted of temperature and volume otherwise known as Charles' Law. 

Charles' Law tells us that temperature and volume vary directly with each other. 

Temperature for all problems must be in kelvins.

0 DEGREES CELSIUS= 273.15 KELVIN

As the temperature of a gas increases, it gains energy. This results in an increase in contacting the sides of the container they are entrapped in. 

http://dvhsgaslaws.weebly.com/uploads/1/2/1/6/12160342/6555896_orig.jpg

The equation for Charles' Law is as follows:

http://thescienceclassroom.org/wp-content/uploads/2013/04/Charless-Law.png

Helpful Links:
Charles' Law
Charles' Law-Science Primer
Charles' Law Simulation

Units of Pressure/Boyle's Law

Blog Post #1

(May 10. 2016)

This next and last!! unit we are covering before the final consists of gases. Overall, this is a pretty simple unit that just contains a lot of concepts and math equations that makes it a bit difficult to wrap your head around. 

Characteristics of gases:

Gases expand spontaneously to fill their container.

Gases are highly compressible.

Gases form homogeneous mixtures.

Gas molecules are relatively far apart from one another and exert little influence on each other. 

Units of Pressure:

http://images.slideplayer.com/7/1711033/slides/slide_9.jpg

Boyle's Law

The relationship between pressure and volume is an inverse relationship.

Holds true at a constant temperature. (Boyle's law doesn't boil.)

http://www.one-school.net/Malaysia/UniversityandCollege/SPM/revisioncard/physics/heat/images/boyleslawformula.png

The indirect relationship between  volume and pressure.
http://www.one-school.net/Malaysia/UniversityandCollege/SPM/revisioncard/physics/heat/images/boyleslawformula.png


Helpful Links:
Animated Boyle's Law
Boyle's Law
Khan Academy-Boyles Law

Phase Changes/Heating Cooling Curves

Blog Post #2

(April 26, 2016)

Our last lecture of this unit presented us with two different types of graphs:

Heating and Cooling Curve: Shows where an element/compound will freeze/boil/melt.

Add caption

http://www.kentchemistry.com/images/links/matter/HeatCool.gif


Things to Know about Heating/Cooling:

• change of state is a physical change    
• melting and boiling points are determined by the vapor pressures of the solid and liquid states
• at 0 degrees Celsius, ice and liquid water have the same vapor pressure.
• at 100 degrees Celsius, water vapor and atm are equal.

Phase Diagram: A representation of the states of a substance in relation to temperature and pressure.

http://d2vlcm61l7u1fs.cloudfront.net/media%2F654%2F654abc63-5ebf-4f33-9507-c38acd719f38%2FphpAsNMSr.png

Things to Know about Phase Diagrams:

• triple point-point at which the solid, liquid, and vapor states all have the same vapor pressure and coexist.
• critical temperature-the temperature above which the vapor cannot be liquefied, regardless of the pressure applied.
• critical pressure-the pressure required to liquefy the vapor at the critical temperature
• critical point-point at which the critical temperature and critical pressure coincide

Useful Links:

Heating and Cooling Curves

Heating Curves

Crash Course-Enthalpy

Measuring Energy Changes

Blog Post #1
Earlier this week, we had started a new unit over Energy and Phase Changes.
Energy changes accompany all chemical reactions and are due to the rearranging of chemical bonds. In fact, addition of energy is always a requirement for the breaking of bonds, but the breaking of bonds in itself, does not release energy. 
Chemists define work as directed energy change resulting from a process.

There are many different types of energy:
Kinetic Energy- energy of motion
Radiant Energy- Energy from the sun or solar energy
Thermal Energy-Energy associated with the random motion of atoms and molecules
Chemical Energy- Energy stored within the structural units of chemical substances
Potential Energy- Energy stored or energy of position

http://mskuksclass.weebly.com/uploads/1/9/7/1/19719395/8207568_orig.jpg

In calculating heat, we typically use the formula Q=mcAt
Q=heat in joules
M=mass in grams
c=specific heat in (J/g degree C)
AT=Change in temperature
https://s-media-cache-ak0.pinimg.com/736x/cd/80/5e/cd805e4fe12071be7b4a7ce04fac0709.jpg

Useful Links:
How To Determine Specific Heat
Measuring the Quantity of Heat

Biodiesel Afterthoughts

Blog Post #3

Looking back over the whole biodiesel unit, It was a fun, quick easy unit to cover and have a 'fun' little project over rather than a test. Over the times I had spent studying and watching multiple biodiesel films and talks about it, I realized just how much biodiesel can change our world.

Useful Links:
Biofuel Facts
Biofuels Fun Facts
13 Strange and Interesting uses of Biodiesel