Search found 22 matches

by Jean Mok 3K
Sun Dec 10, 2017 2:45 pm
Forum: Lewis Acids & Bases
Topic: the importance of protonation
Replies: 2
Views: 174

Re: the importance of protonation

Protonation is the addition of a proton to a molecule, so the molecule would be a base. Conversely, deprotonation occurs to bronsted acids that donate their proton to a base.
by Jean Mok 3K
Sun Dec 10, 2017 2:42 pm
Forum: Octet Exceptions
Topic: Exceptions [ENDORSED]
Replies: 7
Views: 423

Re: Exceptions [ENDORSED]

Octet exceptions can occur when the element is from the third period and beyond because of the accessible d orbitals.
by Jean Mok 3K
Sun Dec 10, 2017 2:40 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7582
Views: 1015194

Re: Post All Chemistry Jokes Here

Q: What do chemists call a benzene ring with iron atoms replacing the carbon atoms?

A: A ferrous wheel.

Cheers! We outta chem 14A.
by Jean Mok 3K
Fri Dec 08, 2017 10:58 am
Forum: Bronsted Acids & Bases
Topic: Neutralization reactions
Replies: 2
Views: 172

Re: Neutralization reactions

When a base and an acid react together to form a salt and a water, it is a neutralization reaction and the pH is driven towards 1.0E-7. The H+ of the acid and the OH- of the salt form water whereas their counterparts form the salt. Hope this helps!
by Jean Mok 3K
Fri Dec 08, 2017 10:49 am
Forum: Lewis Acids & Bases
Topic: Ethylamine vs. Methylamine
Replies: 1
Views: 173

Ethylamine vs. Methylamine

Why is Ethylamine a stronger base than methylamine? I mean beyond the reason of a lower pKb. Why does Ethylamine have a lower pKb?
by Jean Mok 3K
Wed Nov 29, 2017 11:43 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Square planar vs Tetrahedral
Replies: 2
Views: 179

Re: Square planar vs Tetrahedral

A square planar molecule has the molecule notation of AX4E2 where tetrahedral has the molecule notation of AX4. In other words, a square planar molecule has 2 pairs of free electrons.
by Jean Mok 3K
Wed Nov 29, 2017 11:33 pm
Forum: Conjugate Acids & Bases
Topic: Chemical Formula
Replies: 5
Views: 306

Re: Chemical Formula

If the molecule is made with a metal element, then it's a base. If the molecules is made a nonmetal element, it's an acid. You can also see if there are Hydronium ions being produced or hydroxide ions being produced.
by Jean Mok 3K
Wed Nov 29, 2017 11:29 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Weaks vs. Strong acids
Replies: 3
Views: 232

Re: Weaks vs. Strong acids

If you are asking how we know, there is a tendency for acids made with elements on the far right side of the periodic table to be strong acids because of their high electronegativity. But we know them mostly from memorizing them!
by Jean Mok 3K
Wed Nov 29, 2017 11:27 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Square Planar
Replies: 3
Views: 184

Re: Square Planar

They are 90 degrees or 180 degrees.
by Jean Mok 3K
Wed Nov 29, 2017 11:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: From the Post-Module Assessment 1A:
Replies: 3
Views: 176

Re: From the Post-Module Assessment 1A:

To be honest I am not too sure about this exactly but from my understanding there is not much of a difference between the first two things that you quoted. I am not exactly sure about the third.
by Jean Mok 3K
Tue Nov 14, 2017 11:29 pm
Forum: Hybridization
Topic: Purpose of hybridization [ENDORSED]
Replies: 5
Views: 672

Re: Purpose of hybridization [ENDORSED]

The purpose of hybridization is to see the types of bonds that the atoms share with each other, whether it be sigma or pi bonds. The different types of bonds allow different properties, like how pi bonds do not allow rotation whereas sigma bonds are rotational.
by Jean Mok 3K
Tue Nov 14, 2017 11:26 pm
Forum: Hybridization
Topic: Diapole
Replies: 4
Views: 271

Re: Diapole

Dipole moments occur in covalent bonds where electrons are not shared equally. The difference in electronegativity creates a charge difference and dipole moments is the measure of this charge difference. A dipole moment is the charge times the distance between the atoms.
by Jean Mok 3K
Mon Nov 06, 2017 12:23 am
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 10
Views: 407

Re: Lewis Structures

If the question asks for resonance structures you should draw all of them. We only drew 3 because those molecules only had 3 resonance structures. I hope this helped!
by Jean Mok 3K
Mon Nov 06, 2017 12:10 am
Forum: Lewis Structures
Topic: When to use a double bond or triple bond [ENDORSED]
Replies: 6
Views: 3446

Re: When to use a double bond or triple bond [ENDORSED]

It depends on the context! Priority wise you would want to use double bonds to match the number of electrons with the total amount you are supposed to have. Then comes the necessity to have formal charges of zero for each atom. Hope this helps!
by Jean Mok 3K
Fri Oct 27, 2017 1:46 am
Forum: Ionic & Covalent Bonds
Topic: Cations and Anions [ENDORSED]
Replies: 12
Views: 931

Re: Cations and Anions [ENDORSED]

Cations are atoms or molecules with a total positive charge (usually through losing electrons), while an anions are those with a total negative charge (usually through losing electrons).
by Jean Mok 3K
Fri Oct 27, 2017 1:41 am
Forum: Ionic & Covalent Bonds
Topic: Chemical formula?
Replies: 5
Views: 326

Re: Chemical formula?

The chemical formula of compounds can be created using rules that can be generalized used on patterns. These rules can be found in the fundamentals part of the textbook (section D). The two things you ask of, however, are cations and perhaps you mean to ask how to find the charges for them. For tran...
by Jean Mok 3K
Fri Oct 20, 2017 2:49 am
Forum: Photoelectric Effect
Topic: Rydberg
Replies: 11
Views: 648

Re: Rydberg

n(initial)-n(final) gives me a negative frequency. Is this right? You should get a negative number because you are going from a higher energy state to a lower energy state. Quantitatively, you would be subtracting a not as negative number from a negative number. The negative result from this indica...
by Jean Mok 3K
Fri Oct 20, 2017 2:44 am
Forum: Photoelectric Effect
Topic: Energy of Photon [ENDORSED]
Replies: 9
Views: 1728

Re: Energy of Photon [ENDORSED]

If the energy of the photon is exactly equal to threshold energy, or "the energy [required] to remove an electron" as you put it, then the electron is ejected. However, because all of the energy was consumed as work, there is no more energy to translate into kinetic energy, thus the veloci...
by Jean Mok 3K
Fri Oct 13, 2017 2:21 am
Forum: Properties of Light
Topic: Question 1.9
Replies: 3
Views: 217

Re: Question 1.9

Hello Michael,

You are absolutely correct. However, microwaves are not one specific wavelength but rather a range from 1m to 1mm. I hope this answered your question~
by Jean Mok 3K
Fri Oct 13, 2017 2:12 am
Forum: Properties of Light
Topic: Relationship between the frequency of electromagnetic radiation and electrical field
Replies: 2
Views: 177

Re: Relationship between the frequency of electromagnetic radiation and electrical field

I am not too sure, but I will try to explain with my reasoning. If the frequency decreases, then the wave broadens which is correlated to the smaller amplitude and thus less intensity. Because less photons are hitting the metal, then less e- are ejected creating a smaller potential difference in the...
by Jean Mok 3K
Fri Oct 06, 2017 11:48 am
Forum: SI Units, Unit Conversions
Topic: Derived Units
Replies: 4
Views: 310

Re: Derived Units

I think I remember Dr. Lavelle saying although it is good to use dimensional analysis of units to check if we were doing the problem correct and arriving at the correct units of measurement, it is not necessary as long as the final units of measurement are correct (assumed to be in SI units).
by Jean Mok 3K
Fri Oct 06, 2017 11:38 am
Forum: Limiting Reactant Calculations
Topic: Limiting Reactant Calculations [ENDORSED]
Replies: 3
Views: 617

Re: Limiting Reactant Calculations [ENDORSED]

Yeah it seems like you know the general direction to go! You would first find the molar mass of NH3 and the molar mass of O2. Then use the MM you calculated to find the number of moles of each respective reactant. Then, pick a reactant and calculate the needed amount of the other using the ratio fro...

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