Chemistry II test Flashcards
Define and/or explain the following laws
1) 1st law of thermodynamics
Any decrease of energy in a given region of space (system) must be exactly balanced by an increase of energy in another region of space (surroundings)
Define and/or explain the following laws
2) 2nd law of thermodynamics
Entropy is “nearly” conserved, which means any decrease of entropy in a given region of space is almost balanced by an increase in another region. In an isolated system, the entropy never decreases.
Define and/or explain the following laws
3) 3rd law of thermodynamics
It is impossible for any process, no matter how idealized, to reduce the entropy of a system to its absolute-zero value in a finite number of operations.
Define and/or explain the following laws
4) Zeroth law of thermodynamics
If A↔B and C↔B, then A↔B
Define and/or explain the following laws
5) Raoult’s law
Vapor pressure is the sum of the partial pressures.
Define and/or explain the following laws
6) Avogadro’s law
Equal volumes of any two gases at the same temperature and pressure contain the same number of molecules.
Define and/or explain the following laws
7) Ideal gas law
pV = nRT
Pressure, p Volume, V Number of moles, n The gas constant, R The temperature, T
Define and/or explain the following laws
8) Henry’s law
(solubility of gases in liquids)
The solubility of a gas I proportional to the partial pressure of the gas above the solution.
Define and/or explain the following laws
9) Dalton’s law of partial pressure *
The total pressure is given by the sum of individual gas pressure.
Define and/or explain the following laws
10) Boyle’s law *
As volume increases, the pressure of the gas decreases in portion.
Define and/or explain the following laws
11) Charles’ law *
As absolute temperature increases, the volume of the gas also increases in portion.
Define and/or explain the following laws
12) Stefan-Boltzmann law *
The thermal energy radiated by a blackbody radiator per second per unit area is proportional to the fourth power of the absolute temperature and is given by
P/A= σT^4 j/ m^2s
Define/explain the following
1) Reference electrodes (also give examples)
The e. p. of a reference electrode remains constant during the operation of the cell at a given temperature
(e.g. Ag/AgCl-, or the calomel, Hg/Hg2Cl2- electrode).
Define/explain the following
2) Boiling point of liquids
The temperature at which the vapour pressure of a liquid equals the external pressure.
Define/explain the following
3) Critical temperature
The temperature above which it is impossible to liquefy the gas, no matter how high the applied pressure.
Define/explain the following
4) Critical pressure
The minimum pressure needed to liquefy the gas at its critical temperature.
Define/explain the following
5) Gibbs energy (also give equation and the second equation with the relationship to the equilibrium constant)
∆G =∆H - T x ∆S G= Gibbs energy H= Enthalpy T=Temperature S=Entropy
Gibbs energy change combines enthalpy and entropy into a single state function.
∆G =-RTln(K)
Define/explain the following
6) Strong and weak acid (also give examples)
Acid is a proton donor. Strong acids: * HCl, * H2SO4, * HNO3
Weak acids:
* CH3COOH
Define/explain the following
7) Strong and weak base (also give examples)
Bases is a proton acceptor.
Strong bases:
* NaOH,
* Ba(OH)2
Weak base:
*Cl-
Define/explain the following
8) State function
A state function is a property of a system that depends only on the current state of the system, i.e. the initial and final state of the system.
Define/explain the following
9) Pressure
Pressure = Force/Area; P=F/A
10) Lipophillic and lipophobic
- Lipophillic
- Capable of dissolving, of being dissolved in, or of absorbing lipids.
- Lipophobic:
- Detergent is solvated in water. Contrasted to lipophilic or nonpolar.
- Not soluble in lipids, or in non-polar solvents
11) Hypertonic, hypotonic and isotonic solutions
Hypertonic:
Hypotonic:
Isotonic solutions:
12) Emulsion
A mixture of two or more liquids that are normally immiscible (unmixable or unblendable). Emulsions are part of a more general class of two-phase systems of matter called colloids.
