Gas Laws and Unit Conversions

Conversion of Units

• To convert Celsius to Kelvin: C + 273.15K
• To convert Fahrenheit to Celsius: (F-32) 5/9
• To convert Kelvin to Celsius: K - 273.15
• To convert Celsius to Fahrenheit: (C x 1.8) + 32
• 1 atm (atmosphere) is equal to 14.6959 psi
• 1 atm is also equivalent to 760 mmHg/Torr
• 1 atm equals 101,325 Pa
• 1 liter (L) is equal to 1000 milliliters (mL)
• 1 L is also equal to 1000 cubic centimeters (cc)
• 1 cc is equivalent to 1 mL
• 1 cubic meter (m^3) is equal to 1000 L

Boyle's Law

• Pressure and volume of a gas are inversely proportional when temperature is constant
• A hyperbolic curve on a graph exemplifies Boyle's Law
• P1V1=P2V2
• P1= P2V2/V1
• V1= P1V2/P2
• P2= P1V1/V2
• V2= V1P1/P2

Charles’ Law

• The volume and temperature of a gas are directly proportional when pressure is constant
• A diagonal line on a graph exemplifies Charles’ Law
• T1V2=T2V1
• V1= V2T1/T2
• T1= T2V1/V2
• V2= V1T2/T1
• T2= V2T1/V1

Kinetic Molecular Theory

• A gas is composed of a large number of particles, either atoms or molecules
• Gas particles are small and have a vast empty space from each other
• Gas particles move randomly in straight line motion and collide with each other and the container frequently
• The force of collisions of gas particles with the walls of the container causes pressure
• Collisions of gas molecules are perfectly elastic, meaning no energy is lost as friction when molecules collide
• The average kinetic energy of gas molecules is directly proportional to the absolute temperature (Kelvin)
• At the same temperature, the molecules of all gases will have the same average kinetic energy.
• Gases are easily compressed when pressure is applied
• Gases expand when heated and contract when cooled
• Gases exert pressure in all directions on the walls of their container
• Gases have lower densities than solids and liquids
• The attractive forces between molecules (intermolecular) are negligible
• Gases mix evenly and completely when contained in the same vessel

Biomolecules

• Biomolecules are the building blocks of life
• Carbohydrates are the primary source of energy
• Carbohydrates are the most common biomolecules
• Carbohydrates consist of CHO (Carbon, Hydrogen, Oxygen)

Monosaccharides

• Monosaccharides include Glucose (blood sugar)
• Fructose (fruits)
• Galactose (brain sugar)

Disaccharides

• Disaccharides include Maltose (malt sugar, alcohol)
• Lactose (milk sugar)
• Sucrose (table sugar)

Polysaccharides

• Polysaccharides include Starch (bread, pasta)
• Cellulose (vegetables, plants)
• Chitin (mushrooms, shrimp)
• Glycogen (unused energy, stored in liver and muscles)

Lipids (fats and oil)

• Lipids store energy for later use
• Lipids also consist of CHO (Carbon, Hydrogen, Oxygen)
• Triglycerides are the most common type of lipids, making up most of your body fat
• Saturated fats are solid at room temperature, while unsaturated fats are liquid at room temperature

Proteins

• Proteins consist of CHONS (Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur)
• There are 20 amino acids, 11 of which can be synthesized
• 9 amino acids must be supplied
• Histidine is only essential for infants
• Enzymes are biological catalysts
• Saliva is an example of an enzyme
• Monomers are small molecules
• Polymers are large organic molecules
• Proteins are used for repairing bones and muscles

Nucleic Acids

• Nucleic acids consist of CHONSP (Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur, Phosphorus)
• Examples of nucleic acids are Ribonucleic Acid and Deoxyribonucleic Acid

Chemical Formula

• Magnesium: Mg+2
• Sodium: Na+1
• Chlorine: Cl-1
• Calcium: Ca+2
• Oxygen: O-2
• Hydroxide: OH-1

Chemical Equation

• Combination: A + B = AB
• Decomposition: AB = A + B
• Single Replacement: A + BC = AC + B
• Double Replacement: AB + CD = AD + CB
• Combustion: (H2O + CO2)

Balancing Chemical Formula

• Factors affecting the rate of a chemical reaction:
• Concentration: higher concentration, faster reaction
• Temperature: higher temperature, faster reaction
• Surface Area: higher surface area, faster reaction
• Catalyst: a catalyst increases the rate of a chemical reaction