August 2006. Cobalt chloride paper is used to test for the presence of water leaking through tiny cracks in pipes or porcelain. When water is present, the test paper goes from blue to pink. As humidity increases, cobalt chloride changes color from sky blue to purple to pink.

Quite quickly water molecules from the air begin to react with the CoCl2 to convert it into the hydrated form CoCl2. 6H2O. The blue colour will start to fade. As time passes, there will be less water in the air round the paper so the rate at which the CoCl2 hydrates will drop.

on addition of water (that causes the instantaneous dilution, therefore a drop in concentration of the free ions, thus decreasing Q), will shift the equilibrium forward in order to bring Q back to the fixed K value (and vice-versa in the case of water evaporating).

When a system has reached equilibrium, no further changes in the reactant and product concentrations occur; the reactions continue to occur, but at equivalent rates. 5. The concept of equilibrium does not imply equal concentrations, though it is possible.

Note that because water is a liquid, it is omitted from this equilibrium expression.

On the other hand, in a closed vessel or system, water and water vapour are in equilibrium at atmospheric pressure (1.013 bar) and 100°C. For any pure liquid at one atmospheric pressure, the temperature at which the liquid and vapour are at equilibrium is called the normal boiling point of the liquid.

The equilibrium vapor pressure of a substance at a particular temperature is a characteristic of the material, like its molecular mass, melting point, and boiling point. It does not depend on the amount of liquid as long as at least a tiny amount of liquid is present in equilibrium with the vapor.

The number of molecules of a liquid becoming vapour will be equal to the number of molecules condensing into liquid in a closed container. Rate of evaporation of liquid water is equal to the rate of condensation of water vapour. Liquid phase is in equilibrium with its own vapour phase. Water (l) ⇌ Water (g)

When can a dynamic equilibrium exist between a liquid and its vapor? In a system at constant vapor pressure, a dynamic equilibrium exists between the vapor and the liquid. The system is in equilibrium because the rate of evaporation of liquid equals the rate of condensation of vapor.

When a gas changes into a liquid, it is called condensation.

When a liquid is in dynamic equilibrium with its vapor phase, the rates of evaporation and condensation are exactly equal to each other. If you imagine putting a pure liquid into a closed container, the vapor pressure is initially close to zero, and as a result, the rate of condensation is also close to zero.

Actually, the rate of evaporation of water is equal to the rate of condensation of the vapours. It shows there is an equilibrium between the two states. The equilibrium between the vapours and the liquid is attained only in a closed vessel. If the vessel is open, the vapours leave the vessel and get dispersed.

Vapor-liquid equilibrium data is useful for determining how liquid mixtures will separate. Because the liquids have different boiling points, one liquid will boil into a vapor and rise in the column, while the other will stay as a liquid and drain through the unit.

In thermodynamics and chemical engineering, the vapor–liquid equilibrium (VLE) describes the distribution of a chemical species between the vapor phase and a liquid phase. The equilibrium vapor pressure of a liquid is in general strongly dependent on temperature.

The high surface tension of water (water “sticks” to itself, so it doesn’t “want to” evaporate) means water has a low vapor pressure. Vapor pressure is constant when there is an equilibrium of water molecules moving between the liquid phase and the gaseous phase, in a closed container.

Explanation: When liquid water is heated then molecules of water absorb heat and due to this vibration between water molecules increase to greater extent. Thus, we can conclude that the water molecules must gain kinetic energy for liquid water to become water vapor.

Geothermal Power Plants When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam. The steam spins a turbine, which is connected to a generator that produces electricity. The steam cools off in a cooling tower and condenses back to water.

1.2 hours

Yes, moving water can evaporate faster than still water. When water moves, the molecules rub against each other and this will make the water warmer over time. The higher temperature will make the water evaporate more quickly.

The molecules move and vibrate so quickly that they escape into the atmosphere as molecules of water vapor. Evaporation is a very important part of the water cycle. Although the level of a lake, pool, or glass of water will decrease due to evaporation, the escaped water molecules dont disappear.

In the covered glass, the water continues to evaporate just as quickly as it does in the open glass. Because the glass is closed, the number of water molecules in the air increases, meaning more and more of them will bump back into the water, changing back to a liquid. The water molecules don’t leave any faster.