Solution And Colligative Properties Flashcards
What is a solution
Homogenous micture composed of 2 or more substances
What are components of the solution
Solute-minority component
Solvent-majority component it determones physical state of the solution
In what states can solution be
•gas
•liquid
•solid-mainly alloys. Alloys of mercury are called amalgams and can be both liquid and solid
What is saturated solution
Solution at equilubrium with a solid in excess
What is solubility of the solute
Max mass that can be dissolved in a given mass/volume of the solvent at a particular T
How does temperature impact solubility
Of solids increases when T increases. And for the gasses it decreases when the temperature increases
What effect does pressure have on solubility
Little on solids and liquids
But it is important effect on solubility of gases
What law explains solubility of gasses
Henry’s law-mass of gas that can dissolve in a liquid is proportional to its pressure over the liquid.
c=k(H)×p
c=conc.of the gas
k(H)=Henry constant
p=pressure of the gas over the solution in atm
What is dissolution process
It consists of dispersing the particles of the solute in the solvent
Explain which conpounds would mix depending on interacrions between the molecules
The interaction between the solute and solvent have to be stronger than the interactions inside the pure substances.
•A-B=stronger than A-A and B-B, A and B will mix
•A-B are much weaker, wont mix
•if A-B are weaker , they may mix depending on T and composition
Explain like dissolves like
Substances must have similiar intermolecular forces to form solutions.
•non-polar dissolve in non-polar
•polar dissolves in polar
What does partially miscible mean
Wgen compound dissolves in some composituon but not the other
How do molecular substances dissolve
The solute has weak intermolecular forces.
They do not ionize and they can form solution through Lindon interactions,Hydrogen bonds etc. They dont conduct electricity
How do ionic compounds dissolve
Splute is held through solid electrostatic interactions. They are dissolved in polar solvents and are electrolytes(conduct electricity)
What factors determine dissociation of a ionic solid in polar solvent
•lattice energy-higher it is, the lower tendency do dissolve
•ion-dipole interactions(ion of solid and dupoles of the solvent molecule)-higher the interactions, higher tendency to dissolve.
What is solvation process
Process of reorganizing solvent and solute molecules. Ion/molecule is surrounded by solvent molecules
What is hydration
Solvation by water
Can electrolyte be ionic and molecular compound
Yes.
For ionic it does dissociation and for molecular its ionozation
Explain strength of the electrolyte
It can be weak and strong
Strong-completly dissociates its ions in solution
Weak-partially dissociates ions in the solution
How are solvents classified
By polarity
•polar-present a dipolar moment and contain atomic bonds between the atoms with different electronegativity
•non-polar-contains atoms with similiar or same electronegativity
How is polarity of a molecule evaluated
With dielectric constant. If its higher than 15->polar
How are polar solvents devided
•protic-high dielectric constant and high polarity. They have H bonded to O,N,F. Molecules are ready to donate H+ to solutes, by hydrogen bonding
•aprotic-high dielectric constant and high polarity. They do not form hydrogen bonds or donate protons, but they still dissolve many salts
What is concentration
It tells us how much solute is dissolved in particular volume of the solution.
What are types of concentration
•molarity-> n/V(L)
•weight precentage-> mass(solute)×100/mass(solute+solvent)
•parts per million mass(solute)×10⁶/mass(solution); if its billion then 10⁹
•molality-> n/mass(kg)
•molar fraction–> X(a)=n(a)/n(a+b)
