Search found 31 matches

by nelquosey
Mon Jun 11, 2018 6:58 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: T-Shape
Replies: 6
Views: 309

Re: T-Shape

You need to consider that a T shape has different bond angles within it, they are not all identical.
by nelquosey
Mon Jun 11, 2018 6:54 pm
Forum: DeBroglie Equation
Topic: DeBroglie
Replies: 5
Views: 371

Re: DeBroglie

given the mass and the velocity you can use the DeBroglie equation to figure out the object in motion's wavelength. This is useful when you are attempting to figure out the wavelength of a particle or a body of mass.
by nelquosey
Mon Jun 11, 2018 6:48 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Trigonal bipyramidal and octahedral family [ENDORSED]
Replies: 2
Views: 221

Re: Trigonal bipyramidal and octahedral family [ENDORSED]

I think that we should know how to do all the VSEPR shapes that were showcased and worked through in class, and in the homework problems. Good luck (:
by nelquosey
Mon Jun 11, 2018 6:46 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Atom vs lone pair
Replies: 3
Views: 152

Re: Atom vs lone pair

lone pairs each have a negative charge, and they also have to respond to the charges of the atoms, making them push in the directions that they do push in. Think of it as a bunch of magnets of identical charges.
by nelquosey
Tue May 29, 2018 10:50 am
Forum: Ionic & Covalent Bonds
Topic: Double/Triple Bonds
Replies: 8
Views: 398

Re: Double/Triple Bonds

All atoms have the capacity but it depends on the whole molecule. You want to make it as stable as possible.
by nelquosey
Tue May 29, 2018 10:47 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angle
Replies: 9
Views: 345

Re: Bond angle

Think of the electron charge, because electron pairs are negatively charged they repel other negatively charged particles, like other electron pairs. They also repel molecules but not with the same force that they do lone pairs.
by nelquosey
Tue May 29, 2018 10:43 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Cancelling out dipole moments
Replies: 3
Views: 306

Re: Cancelling out dipole moments

I would draw the direction of the arrows, if you look like they are positioned in obvious opposite directions, they cancel out. If it is not obvious I would draw vector diagrams like in high school physics, determine the x and y components and figure out whether or not the directions cancel the magn...
by nelquosey
Sun May 20, 2018 5:34 pm
Forum: Ionic & Covalent Bonds
Topic: Octet rule
Replies: 17
Views: 740

Re: Octet rule

How do you know when atoms can break the octet rule? or which atoms can break the octet rule? These are just exceptions that need to be memorized, but I don't think we need to worry too much about them. just be familiar in general with the idea that there are atoms that do not agree with the octet ...
by nelquosey
Sun May 20, 2018 5:31 pm
Forum: Ionic & Covalent Bonds
Topic: Which is more Ionic
Replies: 2
Views: 138

Re: Which is more Ionic

I googled your question and came across someone who had the same question as you back in 2011:
viewtopic.php?t=4306
I hope the replies help :)
by nelquosey
Sun May 20, 2018 5:26 pm
Forum: Ionic & Covalent Bonds
Topic: 3.25 c)
Replies: 4
Views: 236

Re: 3.25 c)

Hydrogen can either have a charge of positive or negative 1 but since Aluminum already assumes the positive charge, you use the Hydrogen charge of 1- to construct your formula :)
by nelquosey
Mon May 14, 2018 11:19 am
Forum: Photoelectric Effect
Topic: Incoming Light [ENDORSED]
Replies: 4
Views: 351

Re: Incoming Light [ENDORSED]

It is definitely UV light as proven by the Ultraviolet catastrophe.
by nelquosey
Mon May 14, 2018 11:15 am
Forum: Ionic & Covalent Bonds
Topic: VALENCE ELECTRONS [ENDORSED]
Replies: 16
Views: 716

Re: VALENCE ELECTRONS [ENDORSED]

I like to use the group numbers and subtract 10 as we approach the non-metals.
by nelquosey
Mon May 14, 2018 11:14 am
Forum: Lewis Structures
Topic: Dots or lines [ENDORSED]
Replies: 5
Views: 249

Re: Dots or lines [ENDORSED]

I believe that it's fine to use lines since Dr. Lavelle uses dots simply to erase confusion before delving into the concept. I think moving forward we will be using the system of lines in class.
by nelquosey
Mon May 14, 2018 11:11 am
Forum: Electronegativity
Topic: Trends? [ENDORSED]
Replies: 10
Views: 737

Re: Trends? [ENDORSED]

We went over atomic radius, ionic radius, ionic energy and electron affinity in class.
by nelquosey
Mon May 14, 2018 11:09 am
Forum: General Science Questions
Topic: Conceptual Questions
Replies: 4
Views: 303

Re: Conceptual Questions

I find it really helpful to watch videos on the concept, I like Crash Course Chemistry. I watch the video and take notes on it. It's also helpful to explain the concept to other people. If you can explain the concept without using notes you have a full understanding of the concept.
by nelquosey
Sun May 13, 2018 8:19 pm
Forum: Lewis Structures
Topic: Valence shell on Noble gases
Replies: 4
Views: 223

Re: Valence shell on Noble gases

No, Noble gasses have a full valence shell and do not need any electrons to become stable.
by nelquosey
Sun May 13, 2018 8:18 pm
Forum: Ionic & Covalent Bonds
Topic: Ionic vs Covalent vs Metallic Bonds
Replies: 6
Views: 366

Re: Ionic vs Covalent vs Metallic Bonds

An ionic bond is the transfer of electrons from an non-metal to a metal, a covalent bond is when two non-metals share electrons and metallic bond is when a metal exists within a mass of electrons.
by nelquosey
Sun May 13, 2018 8:11 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Equation
Replies: 3
Views: 208

Re: Equation

I would use the one we learnt in class to get my answer and use the high school one to check my answer.
by nelquosey
Sun May 13, 2018 8:05 pm
Forum: Administrative Questions and Class Announcements
Topic: Returned midterms
Replies: 1
Views: 167

Re: Returned midterms

I believe they will be handed back in discussions either way but if you can't make it, go to either your TA's office hours or Dr. Lavelle's :)
by nelquosey
Wed Apr 25, 2018 8:38 am
Forum: Properties of Light
Topic: test 2
Replies: 18
Views: 741

Re: test 2

I would put extra effort into having a full understanding of the concepts. Once you've got calculations down and have done the practice, focus more on the concept behind that calculation. There is no point in practicing redundantly if you don't understand what your calculations mean or what the foun...
by nelquosey
Wed Apr 25, 2018 8:33 am
Forum: Photoelectric Effect
Topic: Difference between photon and particle?
Replies: 2
Views: 158

Re: Difference between photon and particle?

A photon is a packet of energy or light whereas a particle is a subatomic unit such as electron, neutrons and protons. Also, traditionally photons do not have masses whereas particles do.
by nelquosey
Wed Apr 25, 2018 8:29 am
Forum: Photoelectric Effect
Topic: Frequency on Photoelectric Effect
Replies: 5
Views: 273

Re: Frequency on Photoelectric Effect

Since it's a one photon to one atom to one electron interaction increasing the number of photons (increasing the intensity) should increase the number of electrons ejected, this answers your second question. However, you need to keep in mind that different metals have different work functions and th...
by nelquosey
Sun Apr 22, 2018 11:40 am
Forum: Properties of Light
Topic: still don't uderrsatnd what a photon is [ENDORSED]
Replies: 20
Views: 506

Re: still don't uderrsatnd what a photon is [ENDORSED]

I like to think of a photon as a packet of light/energy.
by nelquosey
Sun Apr 22, 2018 11:38 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: 1J=1kg.m^2.s^-2
Replies: 3
Views: 133

Re: 1J=1kg.m^2.s^-2

If you think about the equation for kinetic energy you see that Ek=(1/2)mv^2. (1/2) is a constant and has no units. Mass has units in Kg and velocity is measured in m/s. The equation asks you to square velocity and if you think about your exponent laws (m/s)^2 comes out to be m^2/s^2. This equation ...
by nelquosey
Sun Apr 22, 2018 11:25 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Calculating energy [ENDORSED]
Replies: 3
Views: 177

Re: Calculating energy [ENDORSED]

I suggest using unit cancellation or dimensional analysis to solve questions like these. You have all the equations you need and the givens required to use simple cancellation and number crunching :)
by nelquosey
Thu Apr 12, 2018 9:50 am
Forum: Limiting Reactant Calculations
Topic: Knowing if it's Limiting Reactions
Replies: 6
Views: 345

Re: Knowing if it's Limiting Reactions

I would just be prepared in general with a founded understanding. Also I suggest that you do all the limiting reactant questions that were "assigned" for homework :)
by nelquosey
Thu Apr 12, 2018 9:47 am
Forum: Properties of Light
Topic: HW 1.7 (speed of light) clarification
Replies: 4
Views: 165

Re: HW 1.7 (speed of light) clarification

I believe that the speed of light with the exact number of sig-digs preferred by Dr Lavelle is on the formula sheet given to us in tests :)
by nelquosey
Thu Apr 12, 2018 9:45 am
Forum: Properties of Light
Topic: HW 1.5 [ENDORSED]
Replies: 7
Views: 379

Re: HW 1.5 [ENDORSED]

To calculate anything about frequency or energy you would need to be given wavelength. This question is testing general knowledge of electromagnetic radiation. The question assumes that you know the order.
by nelquosey
Sun Apr 08, 2018 5:38 pm
Forum: Administrative Questions and Class Announcements
Topic: Lecture Outlines [ENDORSED]
Replies: 2
Views: 115

Re: Lecture Outlines [ENDORSED]

I am sure that Dr. Lavelle will make it clear when he switched from one to the other :)
by nelquosey
Sun Apr 08, 2018 5:36 pm
Forum: Limiting Reactant Calculations
Topic: Actual Yield [ENDORSED]
Replies: 3
Views: 169

Re: Actual Yield [ENDORSED]

Because actual yield depends on side reactions, human error, and other experimental mishaps, it is hard with our level of understanding of chemistry to measure actual yield. As of now we have been calculating chemical problems within a very theoretical and almost perfect sphere, where reactions are ...
by nelquosey
Sun Apr 08, 2018 5:30 pm
Forum: Empirical & Molecular Formulas
Topic: Rounding atomic weight (general question) [ENDORSED]
Replies: 8
Views: 496

Re: Rounding atomic weight (general question) [ENDORSED]

In the test we will be given a periodic table and I would assume that we are meant to use whatever version of the atomic mass that the table specifies :)

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