Search found 60 matches

by jvera4b
Sun Dec 08, 2019 7:36 pm
Forum: Bronsted Acids & Bases
Topic: Hydrogen Bonding
Replies: 10
Views: 219

Re: Hydrogen Bonding

No, hydrogen bonding is a type of intermolecular force not a type of acid base reaction.
by jvera4b
Sun Dec 08, 2019 7:35 pm
Forum: Sigma & Pi Bonds
Topic: How to Find Sigma Bonds and Pi Bonds
Replies: 15
Views: 394

Re: How to Find Sigma Bonds and Pi Bonds

Using the Lewis Structure then you can determine which is the central atom (or the one being asked for in the question) and look at the number bonds. The first bond will always be a sigma bond, a double bond has a sigma and pi, and a triple bond will be one sigma and two pi.
by jvera4b
Sun Dec 08, 2019 7:30 pm
Forum: Naming
Topic: -ate
Replies: 10
Views: 232

Re: -ate

Nothing for positive only if the ion is an anion (negatively charged).
by jvera4b
Sun Dec 08, 2019 10:31 am
Forum: Lewis Acids & Bases
Topic: all acids and bases
Replies: 4
Views: 128

Re: all acids and bases

Yes, lewis acid accepts protons and lewis base is the one that gives. A Bronstead acid donates a H+ while a base will a accept the H+.
by jvera4b
Sun Dec 08, 2019 10:26 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Ka only in weak acids and bases?
Replies: 2
Views: 106

Re: Ka only in weak acids and bases?

Ka is only given for weak acids because they don’t dissociate completely so just assume complete dissociation for strong acids.
by jvera4b
Sun Dec 01, 2019 10:41 pm
Forum: General Science Questions
Topic: Bruincasts
Replies: 9
Views: 282

Re: Bruincasts

Lectures are not bruincasted and slides are also not uploaded, but if you want to review past topics Dr. Lavelle does have the Audio-Visual Focus-Topics on the class website.
by jvera4b
Sun Dec 01, 2019 10:33 pm
Forum: Administrative Questions and Class Announcements
Topic: Studying for final exam
Replies: 8
Views: 107

Re: Studying for final exam

Study your lecture notes since in past finals an example from lecture was asked about. I would also recommend going to review sessions whenever you can since there is a lot of material that we must review.
by jvera4b
Sun Dec 01, 2019 10:21 pm
Forum: Naming
Topic: Chelating
Replies: 6
Views: 102

Re: Chelating

Liliana Aguas 3G wrote:What day of lecture notes was this topic mostly covered?

I believe November 20.
by jvera4b
Sun Dec 01, 2019 10:18 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Textbook
Replies: 5
Views: 74

Re: Textbook

Acids and bases are covered in Fundamentals J and Chapter 6.
by jvera4b
Sun Dec 01, 2019 10:16 pm
Forum: Naming
Topic: 9C.1 B
Replies: 1
Views: 33

Re: 9C.1 B

You find the chrage of cobalt by first calculating what the total charge of the hexaammine is (0 since NH3 is neutral) and then the total charge of the complex ion (3+) in this problem that would mean that the charge of cobalt is 3+ hence the answer being hexaammine cobalt(III).
by jvera4b
Sun Dec 01, 2019 10:09 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Acids Vs. Bases
Replies: 11
Views: 170

Re: Acids Vs. Bases

(Bronstead) acids are proton donors while (brontead) bases are proton acceptors.
by jvera4b
Sun Dec 01, 2019 10:01 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sigma Bond
Replies: 10
Views: 117

Re: Sigma Bond

Yes the first bind is always a sigma bind while all other bonds formed will be pi bonds.
by jvera4b
Sun Dec 01, 2019 9:59 pm
Forum: Lewis Acids & Bases
Topic: Strong versus weak
Replies: 5
Views: 76

Re: Strong versus weak

A strong acid completely ionizes in a solution, producing more protons in the solution.
by jvera4b
Sun Nov 24, 2019 9:06 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand
Replies: 10
Views: 118

Re: Ligand

A ligand is a molecule which is attached to a central metal. Ligands make up the coordination sphere.
by jvera4b
Sun Nov 24, 2019 9:05 pm
Forum: Sigma & Pi Bonds
Topic: sigma and pi bonds
Replies: 19
Views: 445

Re: sigma and pi bonds

The first bond made is always a sigma bond while any other bonds made will be pi. (A double bond consists of one sigma and one pi bond. A triple bond consists of one sigma and two pi bonds)
by jvera4b
Sun Nov 24, 2019 8:56 pm
Forum: Naming
Topic: Week 9 and Week 10 HW?
Replies: 21
Views: 257

Re: Week 9 and Week 10 HW?

Does anyone know if the HW for both weeks is due on week 10 for all discussions or only those after Wednesday?
by jvera4b
Sun Nov 24, 2019 8:54 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: T-Shape
Replies: 5
Views: 104

Re: T-Shape

The electron pairs are in the "trigonal planar" part of the molecule because that forms the shape with the least amount of repulsion.
by jvera4b
Sun Nov 24, 2019 8:49 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Intermolecular forces
Replies: 5
Views: 80

Re: Intermolecular forces

You can identify the type of intermolecular forces by looking at the dipole moments of the molecules.
by jvera4b
Sun Nov 24, 2019 8:33 pm
Forum: Lewis Structures
Topic: Bent or Angular?
Replies: 16
Views: 341

Re: Bent or Angular?

The terms are interchangeable since they mean the same thing, just know what they are and you should be fine.
by jvera4b
Thu Nov 21, 2019 12:00 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs linear
Replies: 56
Views: 1147

Re: Bent vs linear

A bent molecule will have a lone pair, or two in the case of AX2E2, on the central atom as opposed to a linear which has no lone pairs around the central atom.
by jvera4b
Sun Nov 17, 2019 10:02 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: vsepr angles
Replies: 10
Views: 75

Re: vsepr angles

Yes, so that, if asked, you can make comparisons between the angles of different shapes.
by jvera4b
Sun Nov 17, 2019 10:00 pm
Forum: Hybridization
Topic: Test 2
Replies: 11
Views: 137

Re: Test 2

I don't think so, the only topics Dr. Lavelle said would be on the test from Monday's lecture are sigma and pi bonds.
by jvera4b
Sun Nov 17, 2019 9:51 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: london forces
Replies: 5
Views: 51

Re: london forces

Since electron's are constantly moving, there is potential for a temporary dipole to be present (the electrons would happen to be more towards one side).
by jvera4b
Sun Nov 17, 2019 9:48 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: This Week Test
Replies: 12
Views: 126

Re: This Week Test

Have we gone over sigma and pi bonds yet? Do we have any more information about what exact material will be tested? Lavelle said he would discuss sigma and pi bonds on Monday. ... so are sigma and pi bonds going to be on the test? I think the TAs said they were trying to have the tests done by Sund...
by jvera4b
Sun Nov 17, 2019 9:42 pm
Forum: Lewis Structures
Topic: Balanced Lewis Structures
Replies: 6
Views: 91

Re: Balanced Lewis Structures

When drawing Lewis structure you should focus on the formal charges that make the molecule the most stable. Since Lewis structures are two-dimensional models the placement of atoms around the central atom isn't the most important aspect when drawing them.
by jvera4b
Sun Nov 17, 2019 9:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Geometry versus shape
Replies: 3
Views: 60

Re: Geometry versus shape

The geometry of a molecule only looks at the number of electron dense areas. However, when looking at the shape you take into account how the lone pairs around the central atom will affect the overall three-dimensional shape because they cause elctron repulsion.
by jvera4b
Sun Nov 17, 2019 9:30 pm
Forum: Resonance Structures
Topic: Formal Charge Question
Replies: 15
Views: 345

Re: Formal Charge Question

They have to sum up to the overall formal charge. Each atom's formal charge may vary but they all have to add up to the same overall charge.
by jvera4b
Sun Nov 17, 2019 9:28 pm
Forum: Student Social/Study Group
Topic: Final Exam
Replies: 10
Views: 181

Re: Final Exam

Yes, the exam will cover the material of all the quarter.
by jvera4b
Sun Nov 17, 2019 9:23 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: Stronger molecular force?
Replies: 2
Views: 44

Stronger molecular force?

Between ion-dipole and h-bonding which is the stronger molecular force? I thought it was ion-dipole because there is a full formal charge however I am not sure if this reasoning is correct.
by jvera4b
Sun Nov 17, 2019 9:12 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: induced dipole
Replies: 4
Views: 40

Re: induced dipole

An induced-dipole occurs when a temporary dipole occurs causing/inducing a dipole in a nonpolar molecule. On the other hand, a permanent dipole occurs when a polar molecule is always more elctronegative than the other molecule.
by jvera4b
Sun Nov 17, 2019 9:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pairs
Replies: 10
Views: 86

Re: Lone Pairs

Lone pairs still affect molecular geometery because they still cause repulsion amongst electrons of other atoms.
by jvera4b
Mon Nov 11, 2019 9:25 pm
Forum: Einstein Equation
Topic: E=hv
Replies: 43
Views: 4510

Re: E=hv

E is the energy of the photon and the work function is the threshold energy, the energy needed to remove an electron.
by jvera4b
Mon Nov 11, 2019 9:19 pm
Forum: Einstein Equation
Topic: E=hv vs E=pc?
Replies: 7
Views: 257

Re: E=hv vs E=pc?

E=hv would be used if the frequency is given or you can find it by manipulating c=(lambda)v, E=pc would be used when the momentum cana be found such as when the velocity or momentum is given.
by jvera4b
Mon Nov 11, 2019 9:16 pm
Forum: Resonance Structures
Topic: What is a Resonance "Structure"
Replies: 12
Views: 337

Re: What is a Resonance "Structure"

A resonance structure would be possible ways to draw the Lewis structure of a molecule which has resonance, multiple bonds can be drawn in different locations, the actual structure would be a blend of all the different structures.
by jvera4b
Sun Nov 03, 2019 8:03 pm
Forum: Electronegativity
Topic: size
Replies: 8
Views: 80

Re: size

Atomic radius increases down a group and decreases across a period(from left to right). Electronegativity decreases down a group and increases across a period (left to right).
by jvera4b
Sun Nov 03, 2019 7:58 pm
Forum: Resonance Structures
Topic: All Molecules?
Replies: 4
Views: 56

Re: All Molecules?

No, resonance structures only occur when bonds can be moved to multiple locations.
by jvera4b
Sun Nov 03, 2019 7:51 pm
Forum: Bond Lengths & Energies
Topic: Strength of Bonds
Replies: 16
Views: 210

Re: Strength of Bonds

Shorter bonds are stronger than longer bonds since short bonds involve more elctrons, this which causes the nuclei to be more attracted. Conversely, longer bonds don't make nuclei as strongly attracted and therefore result in them being easily broken.
by jvera4b
Sun Nov 03, 2019 7:43 pm
Forum: Resonance Structures
Topic: Resonance structures
Replies: 15
Views: 346

Re: Resonance structures

Resonance structures are possible ways that the Lewis structure can be drawn (when there are multiple way to arrange electrons but the arrangement of the atoms doesn't change). A better representation of the structure would be a resonance hybrid/ an average of all the possible structures.
by jvera4b
Sun Nov 03, 2019 7:38 pm
Forum: Lewis Structures
Topic: Drawing Lewis Structures
Replies: 5
Views: 63

Re: Drawing Lewis Structures

When you draw a lewis structure you have to pay special attention to the valence electrons in each atom; they help determine if there are single/double/triple bonds. There is normally a center atom, and that is normally the atom that has the lowest ionization energy. For bonds (when the molecule is...
by jvera4b
Sun Nov 03, 2019 6:53 pm
Forum: Formal Charge and Oxidation Numbers
Topic: The equation
Replies: 3
Views: 60

Re: The equation

A lone pair would be the dots that aren't bonded but are still surrounding the element (those which don't have a line connecting to another element). The L in the formal charge equation would be the number of lone electrons for the element you are calculating it for.
by jvera4b
Sun Nov 03, 2019 6:44 pm
Forum: Trends in The Periodic Table
Topic: Drawing Structures
Replies: 3
Views: 42

Re: Drawing Structures

You know you can draw a chemical structure in several ways you can see multiple bonds in different locations, this is known as resonance. Resonance structures are indicator for more stable structures.
by jvera4b
Sun Nov 03, 2019 6:38 pm
Forum: Lewis Structures
Topic: Single bond
Replies: 2
Views: 30

Re: Single bond

A bond represents that two electrons are being shared by the elements. Two bonds would mean that there are four electrons shared by the elements.
by jvera4b
Sun Nov 03, 2019 6:37 pm
Forum: Bond Lengths & Energies
Topic: Midterm Question
Replies: 5
Views: 84

Re: Midterm Question

In the syllabus it lists that the topics in the Chemical Bonds unit are: (ionic and covalent bonds; Lewis structures of inorganic, organic, and biological compounds; resonance structures; formal charge; Lewis acids and bases; coordinate covalent bonds; octet rule exceptions; ionic versus covalent b...
by jvera4b
Sun Oct 27, 2019 8:23 pm
Forum: Ionic & Covalent Bonds
Topic: HW 2A.21d
Replies: 5
Views: 80

Re: HW 2A.21d

I believe Lavelle mentioned this odd configuration along with one other one that I am forgetting right now. He said that these two configurations are anomalies that we just have to memorize without much further explanation. Some areas of chemistry (and science in general) are proven experimentally ...
by jvera4b
Sun Oct 27, 2019 8:18 pm
Forum: Ionic & Covalent Bonds
Topic: Homework
Replies: 13
Views: 206

Re: Homework

Can we do problems from both sections or must they be exclusively from one?
by jvera4b
Sun Oct 27, 2019 8:10 pm
Forum: Resonance Structures
Topic: Octet
Replies: 13
Views: 231

Re: Octet

An octet would be an atom that has 8 valence electrons, noble gases all have octets. The octet rule refers to elements wanting to bond in order to reach eight valence elctrons and stability, the exceptions are H, He, Li, and Be.
by jvera4b
Sun Oct 27, 2019 7:58 pm
Forum: Lewis Structures
Topic: Choosing the central atom
Replies: 16
Views: 206

Re: Choosing the central atom

The central atom is the one with the lowest ionization energy(decrese down a group and increase across a period).
by jvera4b
Sun Oct 27, 2019 7:55 pm
Forum: Ionic & Covalent Bonds
Topic: Resonance
Replies: 10
Views: 124

Re: Resonance

Resonance doesn't mean that the molecule has different structures, rather that the Lewis structure for it can be arranged in various ways (not just three).
by jvera4b
Sun Oct 27, 2019 7:44 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: p-orbitals
Replies: 11
Views: 125

Re: p-orbitals

Unless otherwise specified by the question, you can just write 1s^2 2s^2 2p^3.
by jvera4b
Sun Oct 20, 2019 10:01 pm
Forum: Quantum Numbers and The H-Atom
Topic: Magnetic Quantum Number
Replies: 5
Views: 74

Re: Magnetic Quantum Number

The thrid quantum number tells us the specific orbital in a subshell, such as whether the electron can be foud in px py or pz.
by jvera4b
Sun Oct 20, 2019 9:18 pm
Forum: Properties of Light
Topic: Equations and Constants
Replies: 6
Views: 102

Re: Equations and Constants

All equations and constants are given in the equation sheet, however derivations of equations are not given so its safer (and better) to know what each variable corresponds to in case a question on the exam requires it and to gain a better understanding of the concepts.
by jvera4b
Sun Oct 20, 2019 9:14 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Neon- electron configuration
Replies: 3
Views: 38

Re: Neon- electron configuration

Elements like neon meet the octet rule meaning they have eight electron in its valence shell. The octet rule states that all elements want to have eight electrons in their valence shell, so neon and other elements like it aren't as likely to bond with other elements.
by jvera4b
Sun Oct 20, 2019 9:06 pm
Forum: Properties of Light
Topic: Next test
Replies: 23
Views: 393

Re: Next test

Yes, according to my TA we will get the equation sheet from the first test for every test.
by jvera4b
Sun Oct 20, 2019 8:59 pm
Forum: Photoelectric Effect
Topic: Speed of Light
Replies: 29
Views: 326

Re: Speed of Light

The speed of light is a constant (2.998 x 10^8) as others have mentioned 3.0 x 10^8 is sometimes used, however it would be better if you used 2.998 x 10^8 so that your sig figs at the end are correct.
by jvera4b
Sat Oct 05, 2019 7:08 pm
Forum: Molarity, Solutions, Dilutions
Topic: Solution problem
Replies: 3
Views: 54

Re: Solution problem

The molarity is given by amount of solute molecules (moles) divided by the volume of the solution (liters), the molar amount of solute would therefore be the numerator.
by jvera4b
Sat Oct 05, 2019 7:03 pm
Forum: Limiting Reactant Calculations
Topic: Amount of Limiting Reactants
Replies: 2
Views: 68

Re: Amount of Limiting Reactants

By definition a limiting reactant is the reactant that will be completely consumed. There will be more of one than the other causing the reaction to stop there. Whatever is left of the reactants would be labeled as excess reactants. If the reactants are equal then they will not limit each other, rat...
by jvera4b
Sat Oct 05, 2019 6:55 pm
Forum: SI Units, Unit Conversions
Topic: Unit Conversion
Replies: 5
Views: 75

Re: Unit Conversion

You can multiply the number of kilograms by 1000 grams since that is the conversion number not in scientific notation (1kg=1000g).
by jvera4b
Sat Oct 05, 2019 6:44 pm
Forum: Empirical & Molecular Formulas
Topic: Ratios of Empirical Formulas
Replies: 3
Views: 76

Re: Ratios of Empirical Formulas

Just try to estimate what would number multiplied by .16 is close to 1. To my understanding, you simply have to be really close to a whole number. In this example, 2.16 * 6 = 12.96 which is close to 13. However, if the factor you use gives you (in the example lets say 3) a result (6.48) that is not ...
by jvera4b
Sat Oct 05, 2019 6:32 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Atoms, Molecules, and Formula Units
Replies: 4
Views: 136

Re: Atoms, Molecules, and Formula Units

You can find atoms, molecules, and formula units using Avogadro’s constant because scientists have determined 6.022x10^23 of atoms/particles/ molecules is equal to 1 mol. You can use the substance’s molar mass to calculate what is being asked for. For example if you were given to find the mass of an...

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