Equilibriums between make in the systems more members

1) Enounce the rule of is made and its I use:

V2 _ARIANZA =C _OMPONENTI - F_{AS I}

where the variance is not other that n° delle variable intensive (the pressure, temperature, concentration) that liberations can be varied without to alter the equilibrium del arrange that is without to provoke the passing of one delle are made present,

while C is the n° minimal of the independent members necessary to describe the composition of every phase of the system.

Such rule is used as an example in order to identify in the systems more members if a determined transition must happen to constant temperature or if this is free to vary.

 

2) Characteristics of the equilibriums liquid - vapor of mixtures:

to) the vapor tension of every member it is proporziona them to the fraction molar and therefore the vapor tension of the mixture is not that the sum of the 2 previous ones.

b) the passage from liquid to vapor does not happen to constant temperature but it interests a data interval of temperatures.

 

3) Describe the aliquot precipitation:

Draft of a process used to the aim to separate 2 members who introduce themselves under mixture shape, substantially consists in the repetition more times of the cycle (to create of the vapor, to cool it, to separate it from the liquid).

 

4) For which mixtures the separation of the pure members through aliquot precipitation is not possible:

For those having mixtures a diagram to butterfly in which the having mixture the composition of the point of union of the 2 wings of the butterfly, comes said azeotropic and is characterized from the fact that the passage from liquid to vapor happens to constant temperature.

 

5) Which law characterizes the solubility of gases in the liquids:

The law of second Henry which the weight of a gas that discioglie in a data dissolvent volume, to one given temperature, is grown proportionally to the partial pressure of the gas in equilibrium with the solution, on condition that the gas does not react chemically with the liquid and the solution sufficiently is diluted.

 

6) Describe the equilibrium liquid-liquid of 2 partially miscible liquids:

There is a zone dictates miscibilità gap to the inside of which not miscelate coexist the 2 are made liquid, such gap can be under one given critical temperature or, in other systems, comprised between 2 critical temperatures.

 

7) Like ripartisce a solute one between 2 not miscible liquids:

To one given to temperature the relationship between the concentration of the solute one in the dissolvent To and the concentration in the B dissolvent it is one constant that comes defined division coefficient. Through removal of the composed dissolvent that ripartisce is possible the complete separation of the 2.

 

8) What is the meaning for miscibilità of a solid one:

The crystal crystal formation agrees that is mixed in which the member To and the B member they are alternated in the crystalline building.

 

9) Describe the equilibrium solid-liquid of 2 miscible members is to the solid state that to the liquid state:

For a pure member the melting point is to constant temperature while for a mixture, the melting point is characterized from an interval of temperatures, this effect comes used in order to study the composition of compounds.

 

10) Describe the equilibrium solid-liquid of 2 miscible members to the liquid state but not to the solid state:

They are mixtures that are behaved like solutions in the sense that as a result of a cooling separates pure the solid dissolvent, for rich mixtures of the compound To, is separated To solid to the pure state, while for rich mixtures of the B dissolvent solid B is separated to the pure state. For solutions instead characterized from a concentration dictates eutectic has the separation to constant temperature of To pure and of pure B it stirs to you mechanically.

 

11) Which it is the usefullness of the melting point:

with) It concurs to establish if a member is to the pure state, in the which case is had that the fusion happens to constant temperature.

b) If 2 solid pure ones have the same melting point concur to establish if draft of the same compound, in fact miscelandoli, if the melting point is various from the solid temperature of fusion of the pure ones, it otherwise means that the 2 composed are various, draft of the same compound.

 

12) Describe the equilibriums solid-solid:

Many discs of a valve with characteristics similar to the equilibriums are equilibriums solid-liquid of systems which are miscible to the liquid state but not to the solid state. For inferior temperatures to a temperature it dictates eutettoide are separated pure and to pure B, while to of over of the eutettoide temperature one of composed pure to the the 2 is separated state and one solid solution.