Download Exam 1 | CHM 152IN - General Chemistry II and more Quizzes Chemistry in PDF only on Docsity!
Solvent
substance that dissolves a solute (highest concentration) ...........component which is doing the dissolving TERM 2
Solute
DEFINITION 2 component which is dissolved in a solution (lowest concentration) TERM 3
Solubility
DEFINITION 3 The maximum amount of solid that can be dissolved in a given amount of solvent at a given temperature. This is a physical constant.of a solute depends on the strength of the intermolecular forces in the solutevsinter-molecularforces between the solute and the solvent. TERM 4
Homogeneous Mixtures
DEFINITION 4 -a mixture consists of 2 or more pure substances like compounds or elements.-one in which the properties of the mixture are constant throughout (like concentration or appearance) TERM 5
Characteristics of
Solutions
DEFINITION 5
- Uniform2. Do notseparateon standing3. Cannot be separated byfiltration4. Have variable composition5. Almost always transparent (not cloudy)6. Can be purified by other physical techniques
Like Dissolves Like:
Polar and ionic solutes dissolve inpolar solvents while non- polar solutes dissolve in non-polarsolvents. TERM 7
Gases Dissolving in Gases
DEFINITION 7 Gases mix readily and distribute themselves equally in the volume they are containedin. The laws that govern the rate that they mix are the Gas Laws and Grahams law ofeffusion. All gases are soluble in one another. TERM 8
H
DEFINITION 8 the change in thermal energy that occurs with a chemical orphysical process. TERM 9
Hsoln
DEFINITION 9 -can be either positive(endothermic) or negative(exothermic).-sum of energy changes (H)-overall enthalpy change TERM 10
Solution Process
DEFINITION 10 Enthalpy Change:1. Solute particles separate from one another (Hsolute)2. Solvent particles separate from one another (Hsolvent)3. Solute and solvent particles mix (Hmix)
Immiscible
Does not dissolve TERM 17
Hydrophobic
DEFINITION 17 Water fearing, not attracted to water TERM 18
Hydrophilic
DEFINITION 18 water loving, attracted with water TERM 19
Exothermic Solution
DEFINITION 19 Negative, will feel warm TERM 20
Endothermic Solution
DEFINITION 20 Positive, will feel cold
Gibb's Free Energy
(G)
G = H - TS (where T is the kelvin temperature)25Celsius= 298K-So if G is negative the process is favored. If it is positive, the process is not favored.The implication is that the solution process may be endothermic but this is offset by afavorable S which makes the G negative. TERM 22
Saturated Solution
DEFINITION 22 A solution that has the maximum amount that can be dissolved in itat a certain temperature. They usually have excess undissolvedsolute present. TERM 23
Unsaturated Solution
DEFINITION 23 A solution that contains less that the solubility limit and haveno excess undissolved solute. Sometimes called dilute. TERM 24
Concentrated Solution
DEFINITION 24 A solution that has a concentration approaching the solubility limit. TERM 25
Supersaturated Solution
DEFINITION 25 A solution containing more than the solubility limit at acertain temp. This is made by heating a solution up toincrease the solubility then cooling it down carefully to keepthe solute in solution.
Work (w)
Object moved through space TERM 32
Heat (q)
DEFINITION 32 Form of energy that flows between 2 objects due to their difference in temperature TERM 33
General rule about Chemical or Physical
Process
DEFINITION 33 for a process or reaction to spontaneously (without any additional energy input) occur it must be energetically feasible for it to occur. That means that there has to be a favorable change in energy for a process to occur naturally. TERM 34
First Law of Thermodynamics
DEFINITION 34 Energy can neither by created nor destroyed. The total amount of energy in the universe is a constant. TERM 35
2 Classifications of Energy:
DEFINITION 35 Kinetic Energy- the energy of motion (joule and calorie is most common used energy unit)Potential Energy- the potential to do work. Can be used to raise an object.
State Function
dependenton the initial and final states and it doesn't matter what happens or what energy changes take place in between. TERM 37
heat lost= -heat gained
DEFINITION 37 Calorimetry:heat lost (system) = heat gained (surroundings) TERM 38
H, enthalpy = to q
DEFINITION 38 At constant pressure*heat transfers from one object to another until the other object is at the same temperature TERM 39
-q reaction = q water + q calorimeter
DEFINITION 39 the heat produced in a chemical reaction is measured in a coffee cup calorimeter containing water
