Thermodynamics and Statistical Mechanics

Relative humidity is reported in percentages. The percentage relates to the amount of water vapor air of a given temperature holds when it is saturated. So the humidity is reported as 50%, if the amount of water vapor in the air is half of what the air could hold at its current temperature.

Electrolysis reactions are not thermodynamically spontaneous and require an external source of energy to drive the reaction. This is because they involve the non-spontaneous process of breaking molecules into their constituent ions, which requires an input of energy.

The total entropy of steam at critical pressure and temperature is equal to 1.0785 btu/lb.

(as liquid water does not exist at critical pressure and temperature the entropy of liquid is 0)

*from Elementary Steam Power Engineering, E. McNaughton, 1923

The Calvin scale is a temperature scale in physics defined as the kelvin temperature shifted by 273.15 units, with its zero point at absolute zero. It is no longer in common use compared to the Celsius or Fahrenheit scales.

Increasing temperature affects a reaction in two ways:

1) at higher temperatures the molecules are moving around faster and collisions and reactions are more frequent, so the reaction - both forward and reverse - speed up.

2) at higher temperatures, the equilibrium state will shift. In some cases it will shift the equilibrium towards the product. In other cases, it will shift it back towards the reactants.

There is a limit to the number of energy transfers in a food chain because with each transfer, some energy is lost as heat due to inefficiencies in metabolism and other biological processes. As energy is lost at each trophic level, there is not enough energy available to sustain a large number of links in a food chain. This is known as the 10% rule, where only about 10% of the energy is transferred to the next trophic level.

An intensive property of a thermodynamic system is a property that is independent of the system's size or quantity. Examples include temperature, pressure, and density. These properties are useful for comparing and characterizing different systems regardless of their size.

Under the concept of elasticity, changes in price lead to changes in quantity demanded or supplied. If demand is elastic, a small change in price results in a proportionally larger change in quantity demanded. If demand is inelastic, a change in price leads to a proportionally smaller change in quantity demanded. Elasticity helps to understand how consumers and producers respond to price changes in the market.

The question makes an incorrect assumption that a gas can not condense.

For most definitions of the terms, "gas" is synonymous with "vapor". Gas can condense - I observed it thousands of times while doing my doctoral an post-doctoral research.

One definition of "vapor" is "A substance diffused or suspended in the air". In this case a vapor would include clouds and smoke where liquid droplets and/or solid particles are suspended in a gas. They would have to be so small that they will remain suspended by the movements and currents within the gas rather than drifting down out of the gas due to gravitational forces. Note that this is NOT the same as condensing

The only other case where you might distinguish between a "gas" and a "vapor" is when one applies a very limited - and not very widely used - definition of "vapor" to define it as a saturated gas. A saturated gas is one that is at the point of equilibrium with a liquid. If you define vapor in that way, then when the term gas was used it would imply that it is not at the equilibrium point. Gases only condense at the equilibrium point.

Note that when you get above the critical temperature and pressure you enter a region in the phase space which is referred to as a "supercritical fluid". Changes in pressure above the critical temperature will not cause a supercritical fluid to condense or vaporize - it will just become more dense or less dense. Likewise changes in temperature above the critical pressure will only change density of the fluid in a continuous manner - never condensing or vaporizing the fluid. It is thus legitimate to ask why a gas may condense but not a supercritical fluid, but the same is not true in trying to distinguish between a gas and a vapor.

It depends on what is also happening. According to PV=nRT where P is pressure, V is volume, n is the number of moles, and R is a constant, as Temperature increases, Volume will too. But the area of a substance is not physically accurate because area is 2-dimensional while volume is 3-dimensional and only 3-dimensional objects can have temperature changes because 2-dimensional objects only exist on paper. Hope that helps!

Other instances of increasing a body's thermal energy include using a microwave oven to heat food by transferring electromagnetic radiation as heat and using friction to warm your hands by rubbing them together, converting mechanical work into thermal energy.

The bird will be best represented as an open system if you include the respiration of the bird and the feathers it drops occasionally. If you neglect those factors you could represent it as a closed system. It will NOT be an isolated system since it does work on its surroundings and its surroundings do work on it - along with some amount of heat transfer from the bird to its surroundings.

For a spontaneous reaction, the numerical value of the Gibbs free-energy change (ΔG) is negative, indicating that the reaction is energetically favorable and will proceed in the forward direction. This negative ΔG means that the system is releasing energy and increasing in entropy during the reaction.

To prevent flame impingement on the vessel being heated, which could damage the vessel. A flame cannot pass through a gauze (or screen). as a proof you could set up a bunsen burner beneath a wire gauze. Turn the gas on and ignite the gas above the gauze. you will notice the flame will stay above the gauze. If you ignite the flame beneath the gauze and lower the gauze into the flame, the flame will not pass above the gauze. Yet, if you light both below and above the gauze you will have flame on both sides. Indicating that flames impinging on the gauze do not burn the gas completely and the gas will pass through the gauze.

Gibb's free energy (ΔG) indicates whether a reaction is spontaneous (ΔG < 0) or non-spontaneous (ΔG > 0) at a given temperature and pressure. A negative ΔG means the reaction releases usable energy, while a positive ΔG means energy input is required for the reaction to proceed. Additionally, the magnitude of ΔG can provide insights into the extent to which a reaction will proceed towards completion.

The enthalpy of air at 700 kPa and 450 K can be determined using specific enthalpy values for these conditions from thermodynamic tables or equations. Without specific values, it is not possible to provide an exact answer.

specific heat

2420 / 10750 = .225 or a Coefficient of Performance (COP) = 22.5

When conducting a Boyle's Law experiment, it is important to ensure that the temperature remains constant, as pressure and volume are inversely proportional only at constant temperature. Care should also be taken to prevent air leaks in the equipment to maintain accurate pressure-volume readings. Additionally, make sure to slowly adjust the pressure in small increments to avoid sudden changes that could affect the results.

The formation of a protein from amino acids is an endothermic reaction, requiring energy input to overcome the energy barrier. The reaction is driven by the entropy gain associated with the increase in disorder as the individual amino acids are linked to form a larger molecule. The Gibbs free energy change (ΔG) for the reaction must be negative for it to occur spontaneously.

That depends on whether you are talking about 1 °C or 1 °F. It also depends somewhat on the type of steel.

Warming carbon steel by 1 °C requires about 0.49 J/kg of steel.

Warming 316 stainless steel 1 °C requires about 0.45 J/kg of steel.

To find the answer for 1 °F, multiply the values by 5/9.

Moderation slows or reduces the energy of neutrons in a nuclear reactor. By doing this, moderation allows continuation of the chain reaction. Neutrons will only cause more fission events when they have a specific range of energy, but they have too much energy when they are first emitted from their precipitating event, hence the need for moderation.

Moderation also regulates the reaction. In the light water moderated reactor, for instance, a common design, water is the moderator. Water is also the heat sink, carrying away the energy of the reaction to make steam which spins turbines and makes electricity. If reactivity were to increase, temperature would also increase, causing an increase in the number of voids in the water. This reduces the effectiveness of the moderator and tends to decrease reactivity. Similarly, if reactivity were to decrease, temperature would decrease, causing voids to decrease, ultimately causing reactivity to increase. Conversely, if the load changes, that will reflect back into the water temperature, causing reactivity to adjust accordingly. It is a self-stabilizing situation.

It is also a safety designed system. If there were a sudden loss of heat sink, such as a turbine load rejection, temperature would go up, causing a decrease in reactivity. If there were a steam line break, causing a depressurization incident, the water would flash to steam and the reactor would go instantly subcritical. In both of these scenarios, there would be time to insert the control rods, forcing the reactor further subcritical, and giving the emergency core cooling systems time to startup.

Knocking in thermodynamics refers to the sound produced in an engine when combustion isn't uniform due to premature ignition of the air-fuel mixture. This can lead to engine damage and reduced efficiency. It is important to control knocking in engines to maintain performance and reliability.

the movement of energy and heat .