Presentation on theme: "Bell Ringer Quiz A gas bubble is squeezed with 7.42 atm of pressure. The bubble started at a size of 2.7 L under STP conditions. What is the size of."— Presentation transcript:
1Bell Ringer QuizA gas bubble is squeezed with 7.42 atm of pressure. The bubble started at a size of 2.7 L under STP conditions. What is the size of the bubble once it is squeezed?0.36 LKnowing that Charles’ Law deals with temperature and volume, what does 2.6 L change to when the temperature is decreased from 200 K to 100 K?1.3 LWhat are the following elements: Hf, Os, Pb, Au, Rn, Fr, WHafnium, Osmium, Lead, Gold, Radon, Francium, Tungsten
2Gay-Lussac Gas Law Ideal Gas Law Important Concepts:Gay-Lussac Gas LawIdeal Gas LawKinetic Theory of GasesIdeal Behavior of Gases
3Boyle’s Law Review Boyle’s Law relates pressure and volume P1V1= P2V2 The relationship between pressure and volume is known as what type of relationship?Inverse RelationshipWhat two variables are held constant for Boyle’s Law?Number of particles and temperature
4Charles’ Law Review Charles’ Law relates volume and temperature The relationship between volume and temperature is known as what type of relationship?Directly ProportionalWhat is held constant for Charles’ Law?Number of particles and pressure
5Absolute Zero and Kelvin Scale Absolute zero is the temperature at which the volume of a gas becomes zero when the a plot of the volume versus temperature for a gas are extrapolated. As expected, the value of absolute zero obtained by extrapolating the data is essentially the same as the value obtained from the graph of pressure versus temperature in the preceding section. Absolute zero can therefore be more accurately defined as the temperature at which the pressure and the volume of a gas extrapolate to zero.A plot of the volume versus the temperature of a gas (when the temperatures obtained are converted from Celsius to the Kelvin scale) becomes a straight line that passes through the origin. Any two points along this line can therefore be used to construct the following equation, which is known as Charles' law.Before using this equation, it is important to remember that temperatures must be converted from C to K
6Gay-Lussac’s LawGay-Lussac was a French Chemist who discovered the relationship between temperature and pressureHe kept volume and the number of particles constantHis testing found that as temperature increases the pressure inside a fixed volume increasesThis relationship is known as a directly proportional relationship
7Gay-Lussac’s LawGay-Lussac’s Law states that pressure in directly proportional to temperature in a closed volume that does not changeHe found that the relationship between pressure and temperature was always constantHe found thatKnowing this he set both sides equal and derived his law:
8Example Problem #1If a container is heated from 100 K to 135 K that had an initial pressure of 689 torr, what is its pressure after being heated?T1 = 100 K T2 = 135 KP1 = 689 torr P2 = x torr
9Practice Problem #1If a steel container has an internal pressure of kPa with a temperature of 273 K is submersed in water. The new pressure inside the container is kPa. The container and the water reach equilibrium. What is the temperature of the water?T1 = 273 K T2 = x KP1 = kPa P2 = kPa
10Combined Gas LawBoyle’s, Charles’, and Gay-Lussac’s Laws deal with pressure, volume, and temperature.In the natural world, is it possible to separate pressure, volume, and temperature?In the natural world, these three variables are intertwined and need to be accounted for when dealing with gas propertiesTo account for this inseparability, a gas law was devised to incorporate all three variables.This gas law is known as the combined gas law which states the following
11Example Problem #2If a balloon was inflated with He at STP conditions and had a volume of 1.0 L was released and reached an elevation where the pressure was 0.86 atm and K, what would the new volume of the balloon be?T1 = 273 K T2 = KP1 = 1 atm P2 = 0.86 atmV1 = 1.0 L V2 = x L
12A New Gas LawWith the discovery of the combined gas law, we are now able to take the final step in the gas laws.Let’s make some observations and deductions about the gas laws.What was always kept constant in all 4 gas laws?Number of particlesWhen each gas law was solved for one half of the equation what was seen to be true?It was found to be a constantIf each gas law keeps the number of particles the same, what would happen if we changed the number of particles?A new gas law would need to be derived
13Deriving the Ideal Gas Law If we add in more gas particles to a balloon, what do you predict will happen to the pressure, temperature, and volume of the balloon?The pressure would increaseThe volume would increaseThe temperature would increaseSince all of these variables increase with an increase in particles what is the relationship between these variables?Directly proportional
14Ideal Gas LawKnowing that volume, pressure, and temperature are directly proportional to the number of particles, we can add number of particles (n) to our previously discovered combined gas law to make this relationship:Without even knowing it, we have derived what is known as the Ideal Gas LawThe constant k in the above equation is known as the gas constant actually known as RR is equal to (L*atm)/(K* )molis back!!
15Ideal Gas LawNow that we know that k = R for the ideal gas law we can now setup the Ideal Gas LawFor this law scientists made n equal to moles and not number of particles to make the math easier to handleKnowing the ideal gas law makes remembering the other 4 gas laws pointless… WHY!?!
16WHY?!?Remembering the other gas laws becomes pointless because if you set the ideal gas law equal to R and the set it equal to itself anything that is held constant on both sides will cancel out.Do you see the other gas laws?
17Example Problem #3A vessel contains 2.87 moles of CO. The volume of the container is 3.8 L and it has a temperature of 243 K. What is the pressure inside the container?
19Question 1What does STP stand for AND what are the values associated with it?Saturated temperature point AND 0 0C at 1 atmStandard temperature and pressure AND 0 0C at 1 atmStanding Tempo Pianissimo and 100 0C at 0 atmStandard temperature and pressure AND 100 0C at 0 atm
20Question 2 What causes gases to not behave ideally? High Pressure Bad upbringingBeing to hotLow temperatureLow pressureImproper measuring
21Question 3What happens to the molecules of gas if the temperature is increased AND what happens to the pressure?The molecules slow downThe molecules stick togetherThe molecules speed upThe pressure decreasesThe pressure increasesThe pressure stays the same
22Question 4 What is the direct measure of average kinetic energy? DensityPressureVolumeTemperatureConductivity
23Question 5 What is an ideal gas? A gas that interacts with its neighbor gas particles, can stop, and stick togetherA gas that elastically bounces, has constant motion, no attraction or repulsionA gas that elastically bounces but stops from time to timeA unstoppable particle that cannot be contained except by the incredible hulk