Search found 46 matches

by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:40 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Boiling Points
Replies: 1
Views: 33

Re: Boiling Points

Several factors go into it. Usually, whatever has the weaker intermolecular forces will have the lower boiling point. For example, if comparing two molecules and one is capable of hydrogen bonding, that one will have the higher boiling point. If one is capable of dipole-dipole interactions and the o...
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:34 pm
Forum: Naming
Topic: Dien - polydentate
Replies: 1
Views: 24

Re: Dien - polydentate

dien is tridentate
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:32 pm
Forum: Naming
Topic: Shorthands
Replies: 2
Views: 24

Re: Shorthands

The shorthand should be used within the formulas so as not to write out the long formula for ethylenediamine, etc, not as a substitute for the name itself.
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:30 pm
Forum: Ionic & Covalent Bonds
Topic: ionic and covalent bonds
Replies: 5
Views: 66

Re: ionic and covalent bonds

Electronegativity and electron affinity are basically the same thing, so yes
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:25 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Shape - 4
Replies: 3
Views: 41

Re: Shape - 4

Just know it can be either. I wouldn't be surprised if you get full points for only listing one or the other, but better be safe than sorry.
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:23 pm
Forum: Ionic & Covalent Bonds
Topic: boiling point
Replies: 3
Views: 57

Re: boiling point

Several factors go into it. Usually, whatever has the weaker intermolecular forces will have the lower boiling point. For example, if comparing two molecules and one is capable of hydrogen bonding, that one will have the higher boiling point. If one is capable of dipole-dipole interactions and the o...
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:19 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: geometry
Replies: 1
Views: 28

Re: geometry

They can be atoms too. For example: Cl-
by Nicoline Breytenbach 3D
Sat Dec 08, 2018 8:16 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Radicals
Replies: 2
Views: 31

Re: Radicals

Radicals are unpaired electrons that are highly reactive and exist only for short periods of time. One way something becomes a radical is if one electron in a pair is ripped away by another molecule.
by Nicoline Breytenbach 3D
Wed Dec 05, 2018 11:02 am
Forum: Sigma & Pi Bonds
Topic: Identifying sigma & pi bonds
Replies: 4
Views: 59

Re: Identifying sigma & pi bonds

Yes, double bonds contain one sigma bond and one pi bond
by Nicoline Breytenbach 3D
Mon Dec 03, 2018 11:08 am
Forum: Lewis Acids & Bases
Topic: Acid/Super Acid & Base/Super Base
Replies: 2
Views: 21

Re: Acid/Super Acid & Base/Super Base

A superacid is any acid stronger/ more acidic than pure sulfuric acid. Similarly, superbases are bases with extremely high basicity.
by Nicoline Breytenbach 3D
Sat Dec 01, 2018 6:44 pm
Forum: Lewis Acids & Bases
Topic: Difference between Lewis and Bronsted
Replies: 5
Views: 69

Difference between Lewis and Bronsted

What's the difference between Lewis acids and bases and Bronsted acids and bases? Which do we work with more in this class? Is there a lot of overlap between the two, or any specific things that don't overlap?
by Nicoline Breytenbach 3D
Sat Dec 01, 2018 6:41 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Water molecules
Replies: 3
Views: 46

Water molecules

Do water molecules form only one hydrogen bond with another water molecule? Or does it use both its hydrogens, forming two separate hydrogen bonds with two other water molecules?
by Nicoline Breytenbach 3D
Sat Dec 01, 2018 6:36 pm
Forum: Naming
Topic: questions about 9C.3 7th edition
Replies: 1
Views: 21

Re: questions about 9C.3 7th edition

OH2 and H20 are interchangeable and refer to the same compound.
by Nicoline Breytenbach 3D
Sat Dec 01, 2018 6:33 pm
Forum: Naming
Topic: 9C.1 7th edition alphabetical order when naming
Replies: 2
Views: 33

Re: 9C.1 7th edition alphabetical order when naming

The ligand names should be in alphabetical order.
by Nicoline Breytenbach 3D
Tue Nov 27, 2018 3:57 pm
Forum: Coordinate Covalent Bonds
Topic: Difference between coordinate covalent and covalent bond
Replies: 3
Views: 58

Re: Difference between coordinate covalent and covalent bond

All coordinate covalent bonds are covalent bonds, but not all covalent bonds are coordinate covalent, if that makes sense. Coordinate covalent bonds are a type of covalent bond where both electrons involved in forming the bond are originally from one of the interacting atoms or molecules, whereas us...
by Nicoline Breytenbach 3D
Tue Nov 27, 2018 3:51 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: maximizing dipole interactions
Replies: 1
Views: 25

Re: maximizing dipole interactions

Because dipoles with opposite charges attract each other, like a magnet. On the other hand, two dipoles with the same charge will repel each other, which would lead to weak interactions between the dipoles
by Nicoline Breytenbach 3D
Tue Nov 27, 2018 3:48 pm
Forum: Lewis Structures
Topic: Complicated Lewis Structures
Replies: 3
Views: 23

Re: Complicated Lewis Structures

I struggle with this too, and I've found that double checking the formal charges helps me a lot.
by Nicoline Breytenbach 3D
Tue Nov 20, 2018 6:20 pm
Forum: Lewis Structures
Topic: Midterm question
Replies: 8
Views: 79

Re: Midterm question

You could either take the average, or simply say less than 140 but more than 120 pm. Both were taken as correct answers
by Nicoline Breytenbach 3D
Tue Nov 20, 2018 6:18 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Test 3
Replies: 10
Views: 143

Re: Test 3

Both outlines 3 and 4!
by Nicoline Breytenbach 3D
Sun Nov 18, 2018 5:29 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: molecular shape and bond angles
Replies: 3
Views: 40

Re: molecular shape and bond angles

When there are lone pairs involved in the molecule, the resulting bond angles will usually be "less than" a specific number, and we don't have to memorize the actual values specifically.
by Nicoline Breytenbach 3D
Thu Nov 15, 2018 10:36 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Effect of Molecular Shape on Lewis Structure
Replies: 3
Views: 31

Re: Effect of Molecular Shape on Lewis Structure

Not really, Lewis structures are 2-dimensional models and thus couldn't perfectly represent a 3-dimensional molecular shape.
by Nicoline Breytenbach 3D
Thu Nov 15, 2018 10:34 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Repulsion Strength
Replies: 5
Views: 55

Re: Repulsion Strength

Basically the degree to which electron lone pairs or bonding pairs repel other lone pairs or bonding pairs, contributing to the overall shape of the molecule. Higher repulsion means the electrons "want to be alone," and thus repel other electrons to a greater degree, sometimes even forcing...
by Nicoline Breytenbach 3D
Tue Nov 13, 2018 12:48 pm
Forum: Administrative Questions and Class Announcements
Topic: Thanksgiving Wednesday
Replies: 9
Views: 180

Re: Thanksgiving Wednesday

michellebui_3L wrote:Does anybody know how we will turn in homework for Week 8 if we have discussion on Thurs/Fri?

We will turn it in week 9!
by Nicoline Breytenbach 3D
Tue Nov 06, 2018 7:14 pm
Forum: Administrative Questions and Class Announcements
Topic: Thanksgiving Wednesday
Replies: 9
Views: 180

Thanksgiving Wednesday

I know the Wednesday before Thanksgiving break (the day before break officially starts) a lot of professors decide to cancel lecture. Does anyone know if we will have lecture in this class on that Wednesday or if we will have it off? I need to make travel arrangements.
by Nicoline Breytenbach 3D
Tue Nov 06, 2018 1:36 pm
Forum: Lewis Structures
Topic: Parenthesis for Ions' Lewis Structures
Replies: 2
Views: 45

Re: Parenthesis for Ions' Lewis Structures

It is a necessary step, and if on a test you were to leave off the brackets and charge in your answer you would likely be docked points. It also helps when drawing the lewis structure of a salt which contains two or more ions, since the different ions must be separated by brackets to obtain the corr...
by Nicoline Breytenbach 3D
Tue Nov 06, 2018 1:32 pm
Forum: Lewis Structures
Topic: Lewis Structure for NO2
Replies: 3
Views: 36

Re: Lewis Structure for NO2

It's because O is more electronegative. Also, usually when there is one of one element and multiple of another, the unique element is in the center (though not always, it's just a trend).
by Nicoline Breytenbach 3D
Wed Oct 31, 2018 7:32 am
Forum: Formal Charge and Oxidation Numbers
Topic: Finding the lowest energy structure
Replies: 5
Views: 91

Re: Finding the lowest energy structure

Calculating and comparing formal charges is the best way to determine the most stable structure!
by Nicoline Breytenbach 3D
Wed Oct 31, 2018 7:29 am
Forum: Lewis Structures
Topic: Stable Lewis Structures
Replies: 4
Views: 57

Re: Stable Lewis Structures

Whichever structure gives the most possible atoms a formal charge of 0, or closest to 0!
by Nicoline Breytenbach 3D
Wed Oct 31, 2018 7:26 am
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 2
Views: 37

Re: Lewis Structures

Lines represent shared or bonded electrons, while dots are used when an electron is unbonded: a "lone pair"
by Nicoline Breytenbach 3D
Tue Oct 23, 2018 12:56 pm
Forum: Student Social/Study Group
Topic: Studying for tests/midterm
Replies: 18
Views: 842

Re: Studying for tests/midterm

I just do all the homework problems at least once, then look over them again in the days leading up to the test. Prof. Lavelle says that if you do all the homework problems you should be well-prepared for the test.
by Nicoline Breytenbach 3D
Tue Oct 23, 2018 12:54 pm
Forum: Administrative Questions and Class Announcements
Topic: test 2
Replies: 5
Views: 199

Re: test 2

Prof. Lavelle also has the outline for the test on his website so you can see everything that will be covered in test 2.
by Nicoline Breytenbach 3D
Tue Oct 23, 2018 12:52 pm
Forum: Properties of Light
Topic: Power calculations
Replies: 6
Views: 152

Re: Power calculations

I sometimes have this same problem, and for me I've discovered it usually has to do with not converting everything to the right units before calculating. For instance leaving something as grams when it should be kilograms can lead to the right number answer except with the wrong power.
by Nicoline Breytenbach 3D
Fri Oct 12, 2018 11:28 pm
Forum: Properties of Electrons
Topic: Wave Particles Duality of Matter
Replies: 4
Views: 36

Re: Wave Particles Duality of Matter

Constructive inference is when two waves interact "in phase," or when their peaks line up together and their troughs line up together. this results in a combined wave of greater amplitude. Think of an ocean wave, if two little waves combine they make a bigger wave. Conversely, destructive ...
by Nicoline Breytenbach 3D
Fri Oct 12, 2018 6:12 pm
Forum: Properties of Light
Topic: Electromagnetic Spectrum: Colors
Replies: 3
Views: 23

Re: Electromagnetic Spectrum: Colors

There aren't clear-cut boundaries between specific colors; but rather, they overlap and blend together. So, 500 nm would be blue-green, or a sort of teal color. Other colors on the spectrum might be mostly blue but a little green, or mostly green but a little blue. And people might classify colors d...
by Nicoline Breytenbach 3D
Fri Oct 12, 2018 6:06 pm
Forum: Photoelectric Effect
Topic: Photoelectric Effect
Replies: 2
Views: 39

Re: Photoelectric Effect

If 1 million high energy photons hit a metal surface, the maximum amount of electrons that could be ejected would be 1 million electrons, not .5 million. This is because the ratio of incoming photons to ejected electrons is 1:1, provided that each of the photons has a high enough energy to cause the...
by Nicoline Breytenbach 3D
Fri Oct 12, 2018 6:01 pm
Forum: DeBroglie Equation
Topic: "Wave-like Properties" of Matter
Replies: 6
Views: 64

Re: "Wave-like Properties" of Matter

In lecture he said that the cutoff for wavelength isn't really an exact number, though the wavelength value he suggested as the cutoff was about 10^-18 or greater. He also said that he wouldn't test us on questions that are close to the cut off value; if the wavelength is too small it will be by a l...
by Nicoline Breytenbach 3D
Mon Oct 08, 2018 12:19 am
Forum: SI Units, Unit Conversions
Topic: Fahrenheit, Celsius, Kelvin
Replies: 3
Views: 112

Re: Fahrenheit, Celsius, Kelvin

Basically, the US (as well as Myanmar and Liberia) are the only countries that still use the imperial system for measurements, including Fahrenheit. Fahrenheit started as a British colonial measurement hundreds of years ago, but by now both the UK and all of its former colonies (except the US) have ...
by Nicoline Breytenbach 3D
Mon Oct 08, 2018 12:03 am
Forum: Significant Figures
Topic: Formula sheet?
Replies: 5
Views: 146

Re: Formula sheet?

I think we just get a periodic table and the scientific constants, not formulas.
by Nicoline Breytenbach 3D
Sun Oct 07, 2018 11:33 pm
Forum: Limiting Reactant Calculations
Topic: Question M3
Replies: 3
Views: 47

Re: Question M3

If only one reactant mass is given, you can assume that that is the limiting reactant. Otherwise, you will need to test to see which reactant is limiting :)
by Nicoline Breytenbach 3D
Thu Oct 04, 2018 8:27 pm
Forum: Significant Figures
Topic: Decimal point
Replies: 14
Views: 204

Re: Decimal point

Yukta Italia 3I wrote:Does that mean 120. has 3 sig figs and 120 has two sig figs?

Yes!
by Nicoline Breytenbach 3D
Thu Oct 04, 2018 12:04 pm
Forum: Empirical & Molecular Formulas
Topic: Polyatomic Ions
Replies: 1
Views: 51

Polyatomic Ions

Should we have all the common polyatomic ions memorized? Or will we be given that information when needed? If we do need it memorized, does anyone have any tricks to remember them more easily?
by Nicoline Breytenbach 3D
Thu Oct 04, 2018 12:00 am
Forum: Significant Figures
Topic: Decimal point
Replies: 14
Views: 204

Re: Decimal point

If it had been 120 instead of 125, for example, 120 is only two significant figures while 120. is three. It has to do with zeroes at the end of numbers
by Nicoline Breytenbach 3D
Sun Sep 30, 2018 9:45 pm
Forum: SI Units, Unit Conversions
Topic: Grams/mole
Replies: 12
Views: 234

Grams/mole

In some places I see grams per mole written as (g/mol) and other places as (g.mol^-1). I'm pretty sure they mean the same thing but I just want to confirm? Also is there a reason to use one notation rather than the other?
by Nicoline Breytenbach 3D
Sun Sep 30, 2018 2:15 pm
Forum: General Science Questions
Topic: First Homework
Replies: 3
Views: 120

Re: First Homework

During Friday's Lecture (Week 1)

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