## Search found 21 matches

Thu Dec 06, 2018 1:15 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: PKa and Pkb vs Ka and Kb
Replies: 4
Views: 1106

### Re: PKa and Pkb vs Ka and Kb

Does calculating PKa and PKb essentially give you the pH of the acid and base, respectively?
Thu Dec 06, 2018 1:12 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: KA, KB values on final
Replies: 3
Views: 169

### Re: KA, KB values on final

How do you interpret the meaning of KA values?
Thu Dec 06, 2018 1:07 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: How can H2O bond with a metal?
Replies: 1
Views: 119

### How can H2O bond with a metal?

17.33: Which of the following ligands can be polydentate? If the ligand can be polydentate, give the maximum number of places on the ligand that can bind simultaneously to a single metal center: a)HN(CH2CH2NH2)2; b)CO32-; c)H2O; d)N(CH2CH2NH2)3 The answer to part C states that H2O can bind with a si...
Tue Nov 27, 2018 1:34 pm
Forum: Ionic & Covalent Bonds
Replies: 2
Views: 196

### Re: MIDTERM WORKED OUT ANSWERS?

Tue Nov 27, 2018 1:30 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Week 8 Worksheet (3A3I3K)
Replies: 5
Views: 669

### Re: Week 8 Worksheet (3A3I3K)

You're great Joyce (-:
Tue Nov 27, 2018 1:27 pm
Forum: Dipole Moments
Topic: dipole moment
Replies: 2
Views: 159

### Re: dipole moment

To add onto this, how do we use the dipole moment to determine polarization?
Thu Nov 15, 2018 1:03 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: What to memorize in VSEPR?
Replies: 8
Views: 418

### Re: What to memorize in VSEPR?

All we really need to memorize are the basic angles of 90, 120, and 109.5, and also how lone pairs can either increase or decrease those angles. We also need to memorize the names of the different types of shapes (e.g. tetrahedral, trigonal pyramidal, seesaw).
Thu Nov 15, 2018 1:01 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Will we have to calculate bond angles?
Replies: 8
Views: 302

### Re: Will we have to calculate bond angles?

During one of the TA sessions I attended, he said all we really need to know is the general angles like 90, 120, and 109.5, and how lone pairs can either increase or decrease those angles.
Thu Nov 15, 2018 12:58 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: 2
Views: 205

### Induced Dipole?

Can someone explain what an induced dipole is? And how that differs from a regular dipole-dipole interaction?
Wed Oct 31, 2018 6:08 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron removal from orbitals question
Replies: 3
Views: 199

### Re: Electron removal from orbitals question

It's a lot more stable for an element to have a half-full s-orbital and a completely full d-orbital than one missing from the d-orbital. I don't completely remember why, but Dr. Lavelle talked about it in class.
Wed Oct 31, 2018 6:00 pm
Forum: Trends in The Periodic Table
Topic: Periodicity on midterm?
Replies: 2
Views: 143

### Re: Periodicity on midterm?

I think probably. Like they might give a few elements and say put them in order of increasing ionization energy.
Wed Oct 31, 2018 5:57 pm
Forum: Photoelectric Effect
Topic: Test 2 Question 3c
Replies: 1
Views: 256

### Re: Test 2 Question 3c

The ejected electron will have a velocity, which means you have to use the DeBroglie equation to find it, not the energy of light equation. Sometimes they can get confused with eachother because they both have wavelength in the equations, but because you know the electron has mass and a velocity, yo...
Thu Oct 18, 2018 11:46 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Absorption/atomic spectra
Replies: 3
Views: 168

### Re: Absorption/atomic spectra

Yes it would still be positive. The negative sign only tells us in what direction the energy is going (away from the nucleus/toward the nucleus). Energy by itself is always positive though.
Thu Oct 18, 2018 11:44 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: 1.15 Homework Problem
Replies: 2
Views: 169

### Re: 1.15 Homework Problem

First, you do that equation twice, once with the initial energy level, next with the final energy level. Then you plug your answers into the equation E(released)=E(initial)-E(final), then plug that answer into wavelength=(hc)/E.
Thu Oct 18, 2018 11:39 am
Forum: Properties of Electrons
Topic: Nodal Plane
Replies: 5
Views: 385

### Re: Nodal Plane

Another way you could think about it is when the p-orbitals (the infinity-shaped looking ones) are about to intersect. Wherever the p-orbitals are about to intersect, there is a nodal plane (2D) between them. This just means that there's ZERO probability of finding an electron there.
Wed Oct 10, 2018 10:04 pm
Forum: Properties of Electrons
Topic: Finding wavelength from a given velocity of an electron
Replies: 2
Views: 232

### Re: Finding wavelength from a given velocity of an electron

I also found this post that has part c worked out, so if you want to look at this one as well!

viewtopic.php?f=16&t=33344&p=107986&hilit=The+velocity+of+an+electron+that+is+emitted+from&sid=503b67247442334fd29256ccbb4dc65f#p107986
Wed Oct 10, 2018 10:01 pm
Forum: Properties of Electrons
Topic: Finding wavelength from a given velocity of an electron
Replies: 2
Views: 232

### Re: Finding wavelength from a given velocity of an electron

I'm not completely sure about the rest of the questions, but for a) The KE is measured in Joules, so you can plug what you found into the equation:
$E=\frac{ch}{\lambda }$

to find the wavelength, where E is what you found and c (speed of light) and h (Planck's constant) are given.
Wed Oct 10, 2018 9:50 pm
Forum: Limiting Reactant Calculations
Topic: Test 1
Replies: 8
Views: 700

### Re: Test 1

I haven't taken the test yet, but I've heard from multiple friends that the difficulty of the tests is almost exactly the same as the modules, and were easier than the homework problems.
Wed Oct 03, 2018 2:32 pm
Forum: Empirical & Molecular Formulas
Topic: Confusion on number of moles
Replies: 4
Views: 230

### Re: Confusion on number of moles

To add on to what the previous posters said, remember to always balance the equation as well. After, you'll usually see that one mol of the reactant can produce multiple moles of the product. In this case, one mol of the reactant produces two moles of the product. Thus, once you find the amount of m...
Wed Oct 03, 2018 2:23 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Moles and Atomic Masses/Weights
Replies: 4
Views: 218

### Re: Moles and Atomic Masses/Weights

Honestly, I've been wondering the same thing. I always thought that atomic mass and molar mass were interchangeable, and that molar mass was usually used for when you needed to calculate the mass of a compound. For example, the atomic mass of C (carbon) is 12, but the molar mass for the molecule CO2...
Wed Oct 03, 2018 2:19 pm
Forum: SI Units, Unit Conversions
Topic: SI Units
Replies: 10
Views: 413

### Re: SI Units

Speaking of the test, does anyone know when the test is going to be?