Unit 3 Chemistry

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Unit 3 chemistry

Ideal gas law; PV=nRT

Temperature (k)

R: Gas constant

Number of Moles of the gas (mol or Mole)

Volume: (L or mL)

Pressure (atm or kPa)

phase Diagram:

Critical point: the point on the phase diagram at which both the liquid and gas phases of a substance have the same density, which means they are indistinguishable.

Normal boiling point: It's the temperature at which a liquid boils at 1 atmosphere of pressure.

Triple point: It is that temperature and pressure at which the sublimation curve, fusion curve and the vaporization curve meet. or the temperature and pressure at which the solid, liquid, and vapor phases of a pure substance can coexist in equilibrium.

Normal freezing point: 32 degrees fahrenheit or 273.15 Kelvin

Critical pressure: occurs at 218 atm in water

Gas laws

Dalton's Laws of partial pressure: If you have a mixture of gases, the total pressure is the sum is all the pressures of each gas; P total= (P1+P2+........)

Combined gas law: It is a combination of Boyle's and Charles' law, where one of the values does not always have to e constant, so you may use any variables

Charle's Law: As gas temperature increases, Volume increases; equation is V1/T1= V2/T2

Boyles Law: As pressure increases, volume decreases; P1 V1= P2V2

Assumptions made for ideal gases

Particles are in constant motion and travel randomly in straight lines, bouncing off one another

Particles have no intermolecular forces

Particles have no volume

Volume

Definition: the amount of space a gas takes up; measured in Liters (L) for gases; possibly measured in mL; 1L=1000 mL

Units of Pressure

KiloPascals (kPa): The normal atmospheric pressure for this is 101.325 kPa

Atmospheres (ATM): Normal atmospheric pressure is one atm

Matter

In order from Solids to a Gas is the Increase in Entropy and Kinetic Energy

Entropy: How much "Chaos" in the molecules of a substance

Plasma

A Gas heated up so intensely that the electrons break away from their distinct atoms

Gas

Indefinite Shape, Indefinite Volume, Very Disorganized

Solid

Liquid

Indefinite Shape, Definite Volume, Less Organized

Difference between Temperature and heat

Units for temperature: Celsius does not work for gas laws so Kelvins should be used K= Celsius + 273

Temperature: Average Kinetic energy of particles in a substance

Hotter substances having faster moving particles

Thermal energy

^t: Change in Temperature (Celsius)

C: Specific heat capacity

Specific heat: The higher the specific heat, the more energy is needed to heat up the substance/ Lower the specific heat= the less energy is needed

How mush energy it takes to heat up one gram of a substance by one degree Celsius

M: mass (g)

Q: heat energy (Joules or calories)

equation Q=mc^t

Intermolecular Forces (IMF's)

They're Forces that act between stable molecules

Gas: Low IMF, so high Entropy

Liquid: Moderate IMF, so moderate entropy

Solid: Strong IMF, so low entropy

Specific heat capacity

Subtopic

Energy

Definition:

Definite shape, Definite Volume, Highly Organized

Phase change Terminology

Evaporation: Liquid to gas; heat added

Depositions: Gas to Solid phase change

Sublimation: From a solid to a Gas

Solidification: From a liquid to a solid; heat is removed; also called fusion

Melting: From a solid to a liquid ; heat is added