## Search found 20 matches

Wed Mar 09, 2016 1:36 am
Forum: Calculating Work of Expansion
Topic: Greater Residual Entropy? Final Exam 2011 1C
Replies: 1
Views: 375

### Re: Greater Residual Entropy? Final Exam 2011 1C

NO has two positions (N=O and O=N with different numbers of electron pairs on the N and O in the two positions). BF3 has only one position because even when rotated the molecule essentially reacts the same. NO has more possible positions than BF3, so its degeneracy is greater and therefore its resid...
Sun Mar 06, 2016 4:04 pm
Forum: *Identifying Primary, Secondary, Tertiary, Quaternary Carbons, Hydrogens, Nitrogens
Topic: Naming
Replies: 2
Views: 795

### Re: Naming

1. Identify the longest carbon chain. 2. Identify all of the substituents. 3. Number the carbons of the parent chain from the end that gives the substituents the lowest numbers. 4. If the same substituent occurs more than once, then give the numbers of the location of each point on which the substit...
Sun Feb 28, 2016 9:28 pm
Forum: *Alcohols
Topic: tertiary alcohol
Replies: 2
Views: 393

### Re: tertiary alcohol

You know this is tertiary because the main chain has only 3 carbons on it when you can only use neo for 5 or more carbons attached to the main chain. It is an alcohol because it has OH attached to it, therefore making this a tertiary alcohol.
Sun Feb 21, 2016 9:32 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Energy vs. Progress of Reaction GRAPH
Replies: 1
Views: 489

### Re: Energy vs. Progress of Reaction GRAPH

No, the second step does not always have a higher energy barrier. On pg 88 of the course reader you can see that the first step is slower, therefore has a higher energy barrier than the second step.
Sun Feb 14, 2016 5:29 pm
Forum: General Rate Laws
Topic: Difference between rate of reaction and unique rate
Replies: 2
Views: 471

### Re: Difference between rate of reaction and unique rate

The unique rate of reaction is the rate of change in the concentration of a reactant or product divided by its stoichiometric coefficient in the balanced equation. I think question 3 is specifically asking about the unique rate of reaction of NO2, so you would divide the rate of reaction of NO2 by t...
Sat Feb 06, 2016 2:20 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: balancing a redox basic vs acid
Replies: 1
Views: 267

### Re: balancing a redox basic vs acid

To balance a redox reaction in a basic solution, you complete the same steps as you would in an acidic solution, but once you balance the equation you need to add hydroxide anions (OH-). 1. Write the half reactions 2. Balance the atoms other than H and O 3. Balance the oxygens by adding H2O 4. Balan...
Sun Jan 31, 2016 8:03 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Electrons in oxidation and reduction reactions
Replies: 1
Views: 332

### Re: Electrons in oxidation and reduction reactions

The 2e- means 2 single electrons
Sat Jan 23, 2016 6:00 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Comparing Molar Heat Capacities of Substances
Replies: 1
Views: 258

### Re: Comparing Molar Heat Capacities of Substances

Yes, molar heat capacity is higher for a substance that is more complex. This is because as more atoms are present in the molecule, there are more possible bond vibrations that can absorb added energy.
Sun Jan 17, 2016 8:58 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Calculating Time Needed to Burn Energy
Replies: 1
Views: 304

### Re: Calculating Time Needed to Burn Energy

First you need to convert 17.0 kJ/g to kJ/oz. 1 oz=28.3496 grams, so (17.0kJ/g)(28.3496g/1oz)=481.9415 kJ/oz. You then multiply this amount by 2 because you are calculating for a 2.0 oz serving of cheese. (481.9415 kJ/oz)(2.0 oz)=963.883 kJ Then, you plug this energy into the equation Time=Energy/Ra...
Sun Jan 10, 2016 4:02 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Change in Internal Energy
Replies: 4
Views: 1787

### Re: Change in Internal Energy

The gas sample in the cylinder is supplied with 524 kJ of energy, so this is added energy. A piston compressing the gas is also added energy to the system. Therefore you must add both the energy changes given, resulting with an internal energy change of 864 kJ.
Mon Nov 30, 2015 11:19 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: reverse icebox question
Replies: 1
Views: 299

### reverse icebox question

In an icebox problem how can you tell if the reaction is forward or reverse? (how do you know whether to add or subtract x?) Is it likely to get a reverse reaction question on the final?
Sat Nov 28, 2015 11:39 pm
Forum: Bronsted Acids & Bases
Topic: Identifying Bronsted acids and bases
Replies: 1
Views: 475

### Identifying Bronsted acids and bases

NH4I(am) + KNH2(am) -> KI(am) + 2NH3(l)

In this reaction how can you tell which is the Bronsted acid and which is the Bronsted base?
Sat Nov 21, 2015 11:27 pm
Forum: Amphoteric Compounds
Topic: polyprotic
Replies: 1
Views: 343

### Re: polyprotic

Polyprotic acids and bases are unique in a sense that they possess multiple H+ or OH-, respectively, and can disassociate multiple times in solution. For example, Sulfuric acid, H2SO4-, will disassociate to form HSO4- and H+ in solution. In many cases, the initial acid would disassociate to form H+ ...
Sun Nov 15, 2015 10:08 pm
Forum: Naming
Topic: Naming question
Replies: 1
Views: 241

### Re: Naming question

The name is Triamminetrichlorocobaltate (II).
Thu Nov 12, 2015 10:08 pm
Forum: Naming
Topic: Metals and Ligands in Coordination Compounds
Replies: 2
Views: 394

### Re: Metals and Ligands in Coordination Compounds

Yes, that is correct.
Tue Nov 03, 2015 7:48 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: square pyramidal bond angle
Replies: 2
Views: 1326

### Re: square pyramidal bond angle

The bond angles for square pyramidals are less than 90 degrees and less than 180 degrees.
Sun Nov 01, 2015 8:02 pm
Forum: Ionic & Covalent Bonds
Topic: KCl vs FrCl
Replies: 1
Views: 492

### Re: KCl vs FrCl

KCl has a greater covalent character. This is because the difference in electronegativity between K and Cl is smaller than the difference in electronegativity between Fr and Cl.
Tue Oct 13, 2015 2:41 pm
Forum: Empirical & Molecular Formulas
Topic: finding moles of an atom from a compound
Replies: 1
Views: 389

### Re: finding moles of an atom from a compound

89 g HCl x (1 mol/36.461 g)=2.4 mol HCl
From the compound you know there is one mole of H in every mole of HCl
So, 2.4 mol HCl x (1 mol H/1 mol HCl)= 2.4 mol H in 89 g of HCl.
Tue Oct 06, 2015 8:22 pm
Forum: Properties of Electrons
Topic: Conversions [ENDORSED]
Replies: 4
Views: 589

### Re: Conversions[ENDORSED]

1 eV= 1.602x10^-19 J

So the energy in joules E(J) is equal to the energy in electron-volts E(eV) times 1.602x10^-19:
E(J) = E(eV) × 1.602176565x10^-19
Fri Oct 02, 2015 6:06 pm
Forum: *Shrodinger Equation
Topic: psi and psi^2?
Replies: 1
Views: 3336

### Re: psi and psi^2?

psi represents the height of a wave at position x, y, z
psi^2 represents the probability of finding an e-