No. There are several sources of the energy when there is net flow from the bottom to the top of H2O molecules. One source, which gets the process started, is the energy stored in the salt when the sun evaporated the water from it to make salt crystals.
Yes, one is the pressure difference that I mentioned. The salt will add some energy to the system, but this is not the point.
Initially the hydroscopic properties of the salt will remove H2O from the moist water vapor at the top. Then the water in the tank at the bottom will evaporate more H2O molecules and cool, so in addition to the chemical binding energy of the salt crystal, thermal energy is being removed at the bottom.
As the salt removes H2O, more water will drip at the bottom. Thermal energy is being removed via evaporation and deposited via condensation. Evaporation/condensation are the same phenomenon but performed backwards.
Eventually the colder bottom water will have the rate of H2O molecules leaving it equal to the rate water vapor molecules are entering the water in the bottom tank - I.e. the level of the water in the bottom tank will cease to drop.
Colder bottom water? A temperature difference? Another perpetual motion machine?
Indeed, there will only be a slight drop in the water level before it is replenished at equilibrium.
That was a gravitational energy loss, which also helps drive the system.
There was a net gain in gravitational potential energy of water due to evaporation. Evaporation is caused by heat.
Likewise, the rate at which H2O molecules are escaping the "grasp" of the salt solution in the tray at the top will equal the rate at which the H2O molecules in the slight less dense (due to gravity) vapor (moist air) at the top are being captured by the salt water solution in the top tray. I.e. eventually at every station from the water surface at bottom to the surface of the salt water in the tray at the top, the net flow of H2O molecules is zero.
Yes, there will be equilibrium. However, a part of this equilibrium will be dripping water, IE kinetic energy. Initially, there is only thermal energy; as the system progresses towards equilibrium gravitational potential and kinetic energy increase at the cost of thermal energy.
All the mass of H2O that was lifted against gravity is a gain of mgh in its potential energy, but the thermal energy in the water (and even the moist air above it) is reduced to achieve part of this gravitational gain. The remaining part comes from the solar energy stored in the dry salt crystal you initially charged the system with.
Yes, thermal energy is converted to a different kind of energy, namely gravitational potential.
The salt acts as a catalyst, and I'm not sure if it's energy is in any way transformed.
If after equilibrium is established you were to open the well insulated system and restore the initial conditions for a second run to the steady state, you will need to heat the salt solution with more energy than the gravitation energy it produced in the first cycle to get the dry salt crystals back again. You will also need o re-warm the bottom water etc.
If you open the system, there will still be some kinetic energy stored in the form of dripping water. If you added extra thermal energy and close the system, it may have a higher amount of energy that it did initially.
As you should expect - this system requires net input of thermal energy to close the cycle as you are converting thermal energy into gain of gravitational energy, not very efficiently at that.
No, you do not need to add any thermal energy. There is already thermal energy inside of the system at the beginning. A part of this energy is then converted to gravitational potential and then kinetic energy.
It is really not differ than burning some wood in a boiler to produce work. The sun supplied the energy to grow the tree. In this case, if you get your salt from a salt deposit, the sun was the source of the energy for the first cycle. You will burn natural gas, or nuclear fuel, to reproduce the starting conditions for the second and subsequent cycles.
Incorrect. No energy is required, as no energy is created. Thermal energy is transformed to gravitational potential which is then released in the form of kinetic energy, which then causes friction/waves as the water droplets fall back into the bottom tank, this releases all energy as thermal once again. Due to the cyclic nature of the system, a proportion of the energy will always be kinetic, thus, perpetual motion
Unfortunately, there is no free (energy) lunch. Most of it, including nuclear, came from some sun or gravitational collapse and mankind is helping nature degrade it into heat.
Once again, heat is not any any different than other forms of energy; in the right circumstances heat is converted to kinetic energy, just like in the right circumstances kinetic energy is converted into heat.
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