## Search found 20 matches

Tue Dec 05, 2017 11:38 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Acid and Base equations
Replies: 2
Views: 253

### Re: Acid and Base equations

The net ionic equation shows only the chemical species that are involved in a reaction, while the complete ionic equation also includes spectator ions.
Tue Dec 05, 2017 11:18 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 12.67
Replies: 1
Views: 196

### Re: 12.67

I think you can use tables 12.1 and 12.2 in order to find the appropriate Ka and Kb values :)
Thu Nov 30, 2017 12:12 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ch 11 11.13
Replies: 2
Views: 226

### Re: ch 11 11.13

Q is given using partial pressures in this problem because partial pressures should be used when the reaction is in gas phase (g). Concentrations should be used for reactions occurring in the solution phase when the participants are aqueous (aq). I hope this helped :)
Thu Nov 30, 2017 12:08 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Problem 11.45
Replies: 1
Views: 197

### Re: Problem 11.45

In order to solve this problem, you have to set up an ICE box :) First, you have to calculate the initial concentration of Cl_{2} . You can do this by converting 2.0 mmol to moles, which should give you 0.002 mol. Then, to find the initial concentration, you divide 0.002 mol by 2.0 L, which should g...
Wed Nov 22, 2017 1:54 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Chemical Equilibrium
Replies: 2
Views: 211

### Re: Chemical Equilibrium

Pure solids and liquids are not included in the equilibrium constant expression because they do not affect the reactant amount at equilibrium in the reaction. Therefore, they are disregarded and excluded from K.
Wed Nov 22, 2017 1:11 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 11.3 [ENDORSED]
Replies: 1
Views: 214

### 11.3[ENDORSED]

For problem 11.3, the problem asks to write the equilibrium expression K for each of the following reactions. Initially, I wrote K in terms of concentration. However, the solutions manual wrote K in terms of partial pressure. Is there a difference between the two if the problem just asks for K? Than...
Wed Nov 15, 2017 2:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: 2 Lone Pairs and 2 Bonding Pairs vs 1 Lone Pair and 2 Bonding Pairs
Replies: 2
Views: 222

### Re: 2 Lone Pairs and 2 Bonding Pairs vs 1 Lone Pair and 2 Bonding Pairs

The bond angle for a bent molecular shape and a trigonal planar electron geometry would be slightly less than 120 degrees while the bond angle for a bent molecular shape and a tetrahedral electron geometry would be less than 109.5 degrees.
Wed Nov 15, 2017 1:58 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs Angular
Replies: 7
Views: 513

### Re: Bent vs Angular

Yes, the terms bent and angular are interchangeable.
Wed Nov 08, 2017 12:45 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: The configuration of tungsten
Replies: 2
Views: 364

### Re: The configuration of tungsten

According to Dr. Lavelle, the gain in stability from promoting an s electron to half-fill a d-subshell is no longer large enough to be favorable for tungsten so the Cr effect no longer happens.
Wed Nov 08, 2017 12:39 am
Forum: Trends in The Periodic Table
Replies: 6
Views: 434

The atomic radius of an element is half the distance between the centers of neighboring atoms while ionic radius is its share of the distance between neighboring ions in an ionic solid.
Thu Nov 02, 2017 12:37 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration for Tungsten [ENDORSED]
Replies: 1
Views: 167

### Electron Configuration for Tungsten[ENDORSED]

For homework problem 2.43, I expected tungsten to follow the same rule as chromium where it is more stable with a half-complete d-shell. However, the solution manual says that the electron configuration for tungsten is [Xe]4f^{14}5d^{4}6s^{}2 . I was just wondering why tungsten does not follow the s...
Thu Nov 02, 2017 12:31 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Exceptions to the Configuration Rules
Replies: 3
Views: 262

### Re: Exceptions to the Configuration Rules

For electron configurations, I'm pretty sure copper and chromium are the only two exceptions that we need to know :) However, the elements below copper and chromium also follow the same trend, such as silver, so I would keep an eye out for those too!
Tue Oct 24, 2017 10:10 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: ch 2, 47, part d
Replies: 2
Views: 257

### Re: ch 2, 47, part d

In the lecture, Dr. Lavelle talked about how there are two main exceptions to electron configurations. One of the examples that he gave was Cu. In this case, Au is similar to the Cu exception. The full d^{10} subshell turns out to have a lower energy. Therefore, Au has the electron configuration of ...
Tue Oct 24, 2017 9:54 pm
Forum: Trends in The Periodic Table
Topic: Are Trends always consistent?
Replies: 1
Views: 178

### Re: Are Trends always consistent?

Yes, there are other cases in which the trends have had some exceptions to the rules. For example, oxygen has a lower ionization energy than nitrogen even though ionization energies are supposed to increase across a period.
Thu Oct 19, 2017 1:41 am
Forum: Properties of Light
Topic: the quantum world
Replies: 7
Views: 479

### Re: the quantum world

I don't believe that we need to know the specific wavelengths for each radiation type, but it would be good to have a general idea about the different radiation types, especially which radiation types have longer wavelengths and which ones have shorter wavelengths.
Thu Oct 19, 2017 1:34 am
Forum: Properties of Light
Topic: Homework 1.9
Replies: 2
Views: 242

### Re: Homework 1.9

The different frequencies of visible light also determine the color of the visible light :) I think Professor Lavelle mentioned that we did not have to know the specific wavelength for each color, but it would be good to know that 700 nm is red light and 400 nm is violet light.
Thu Oct 12, 2017 12:32 am
Forum: Properties of Light
Topic: HW Problem 1.3
Replies: 4
Views: 340

### HW Problem 1.3

In HW Problem 1.3, the problem asks if a decrease in the frequency of electromagnetic radiation would cause a decrease in the extent of the change in the electrical field at a given point. What is the relationship between frequency and the extent of the change in the electrical field?
Thu Oct 12, 2017 12:23 am
Forum: Properties of Light
Topic: 1.23
Replies: 4
Views: 365

### Re: 1.23

First, you would convert 140.511 keV to eV. 1 keV is 1000 eV, so you can do this by multiplying 140.511 X 1000 = 140.511 X 10^3 eV. Next, you would convert the energy from eV to Joules. 1 eV is 1.6022 x 10^-19 J, so you can convert the energy by multiplying 140.511 X 10^3 eV by 1.6022 X 10^-19 J/eV....
Fri Oct 06, 2017 6:10 pm
Forum: Balancing Chemical Reactions
Topic: Diatomic Molecules
Replies: 3
Views: 959

### Re: Diatomic Molecules

My high school teacher also taught me an easy way to remember the seven diatomic molecules using an acronym :)

Have (Hydrogen)
No (Nitrogen)
Fear (Fluorine)
Of (Oxygen)
Ice (Iodine)
Cold (Chlorine)
Beer (Bromine)