## Search found 14 matches

Sun Feb 28, 2016 7:16 pm
Forum: *Alkenes
Topic: Geometric Isomer
Replies: 1
Views: 330

### Re: Geometric Isomer

This website has a good description of what you are asking https://www.utdallas.edu/~scortes/ochem/OChem1_Lecture/Class_Materials/05_orbitals_hybrid_geom.pdf"onclick="window.open(this.href);return false; Here is a bit of the explanation provided by the website: "When atomic orbitals (pure or hy...
Tue Feb 23, 2016 7:53 pm
Forum: *Alkanes
Topic: IUPAC
Replies: 3
Views: 488

### IUPAC

When naming an organic compound with more than one substituent, how do you know which one is placed first in the name?
Sun Feb 14, 2016 8:14 pm
Forum: Second Order Reactions
Topic: Second Order Concentration
Replies: 1
Views: 400

### Re: Second Order Concentration

For a second-order reaction, the rate of reaction is directly proportional to the square of the concentration of one of the reactants. This is why it is squared.

Differential Rate Law: r = k [A]^2

The rate constant, k, has units of L mole-1 sec-1.
Sun Feb 07, 2016 12:55 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: The Notation for Cells
Replies: 1
Views: 309

### The Notation for Cells

When analyzing the diagram for a cell, how do you know whether the diagram represents the right-handed electrode or left-handed electrode?
Mon Jan 25, 2016 10:24 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Molar Heat Capacity
Replies: 1
Views: 348

### Molar Heat Capacity

Why are the molar heat capacities of gases composed of molecules (as distinct from atoms) higher than those of monatomic gases?
Mon Jan 11, 2016 1:09 pm
Forum: Phase Changes & Related Calculations
Topic: Enthalpy and Entropy
Replies: 3
Views: 485

### Re: Enthalpy and Entropy

Entropy is a measure of disorder or randomness of a system. An ordered system has low entropy. A disordered system has high entropy. Enthalpy is defined as the sum of internal energy of a system and the product of the pressure and volume of the system.
Fri Jan 08, 2016 8:59 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Standard Enthalpy of Formation
Replies: 1
Views: 243

### Re: Standard Enthalpy of Formation

Enthalpy is the total heat content of a system whereas the standard enthalpy of formation is the CHANGE in the heat content of a system when one mole of a substance in the standard state (1 atm of pressure and 298.15 K) is formed from its pure elements under the same conditions.
Mon Nov 30, 2015 10:19 pm
Forum: Conjugate Acids & Bases
Topic: Increasing Acidity
Replies: 3
Views: 833

### Re: Increasing Acidity

The tendency of an atom to draw electrons toward itself increases as the oxidation number of the atom increases. For example, for HClO 4 , as the oxidation number of the chlorine atom increases, the atom becomes more electronegative. This tends to draw electrons away from the oxygen atoms that surro...
Sun Nov 29, 2015 8:18 pm
Forum: Conjugate Acids & Bases
Topic: Increasing Acidity
Replies: 3
Views: 833

### Re: Increasing Acidity

Because the H is always bonded to one of the oxygens in oxyacids, any factor that weakens the O-H bond makes the substance more acidic. As the number of oxygens bonded to the central atom increases, the oxidation number of the central atom increases. This causes a weakening of the O-H bond strength ...
Tue Nov 17, 2015 9:40 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Video: Lewis Structures and VSEPR
Replies: 5
Views: 805

### Re: Video: Lewis Structures and VSEPR

Lewis Structures.m4v [ 292.63 MiB | Viewed 757 times ]

Video:Lewis Structures and VSEPR :uploaded version
Mon Nov 09, 2015 6:50 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Cis and Trans
Replies: 1
Views: 382

### Re: Cis and Trans

For geometric isomers, cis and trans indicate where individual atoms are located. An isomer with the prefix cis- indicates that two atoms are on the same side of a molecule. An isomer with the prefix trans- indicates that the two atoms are across from each other. For example, cis 1,2 dichloroethene ...
Mon Nov 09, 2015 2:45 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Video: Lewis Structures and VSEPR
Replies: 5
Views: 805

### Video: Lewis Structures and VSEPR

Participants:
Sara Buchting - Discussion 3K
Lauren Garcia - Discussion 4L
Samantha Geere - Discussion 3F
Sun Oct 25, 2015 2:09 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Period 3 Elements
Replies: 1
Views: 269

### Re: Period 3 Elements

Period 3 elements are able to accommodate 5 or more electron pairs (more than 8 valence electrons) because they have d-orbitals in their valence shells.
Sat Oct 10, 2015 9:34 pm
Forum: Limiting Reactant Calculations
Topic: Limiting Reactants & Limiting Reagents [ENDORSED]
Replies: 7
Views: 3037

### Re: Limiting Reactants & Limiting Reagents[ENDORSED]

There is a subtle difference. A reactant is a directly reacting substance present at the initiation of the reaction whereas a reagent is a substance participating in a chemical reaction. While all reactants are considered reagents not all reagents are considered reactants (ex: solvents and catalysts).