evaporation and vapour pressure

. In such a state, although the amount of liquid level in the vessel does not change, evaporation has not stopped and the system is not at rest. In fact, the number of molecules, which escape from the liquid to the gaseous phase (due to evaporation), becomes equal to the number ..

Vapour pressure is defined as the partial pressure exerted by the vapors above the liquid surface in equilibrium with liquid at a given temperature. fig 3.3 In illustrations 1a and 1b, the liquid and vapor states of a given substance are represented. The individual mol..

When a liquid is placed in an open container it disappears completely after some time. However, when the same liquid is placed in a closed container, even after a long period only a part of the liquid disappears. The obvious difference is that the vapours of the liquid held in an open con..

Vapour density is the ratio of the mass of a volume of a gas, to the mass of an equal volume of hydrogen, measured under the same conditions of temperature and pressure. According to Avogadro's law, equal volumes of all gases contain equal number of molecules. Thus, let the n..

>The capacity of air to retain water vapour increases with increase in temperature. A rise in temperature causes the rate of evaporation to increase. Thus, many coastal areas have a higher percentage of humidity in summer than in winter. The mass of water vapour presen..

According to the Le Chatelier's principle, this will make the system move in a direction of lower volume. An increase in pressure on the system will result in the condensation of vapours to give liquid, since, liquids have lower volume as compared to vapours. The equi..

Let us suppose a small amount of a non-volatile solute (sugar) is dissolved in a solvent (water). When evaporation of this solution takes place, only water evaporates as the other component (i.e., sugar) is non-volatile. The vapor pressure of the solution is found to ..

According to the Le Chatelier's principle, this will make the reaction move in a direction which absorbs heat i.e., the endothermic process will be favoured. As vaporization (liquid g vapours) is an endothermic process, a rise in temperature will favour the process of vaporization i.e. m..

Vapour pressure is defined as the partial pressure exerted by the vapors above the liquid surface in equilibrium with liquid at a given temperatur..

The total vapor pressure, P exerted by the solution is the sum of P A and P B as required by Dalton's law of partial pressures. P = P A + P B or P = P o A c A + P o B c B = P o A (1- c B ) + P o B c B [because c A + c B = 1] = P o A - P o A c B + P o B c B P = (P o B - P o A ) c..