Search found 51 matches

by Tiffany Dong_4e
Sat Dec 07, 2019 10:39 pm
Forum: Administrative Questions and Class Announcements
Topic: final exam
Replies: 9
Views: 158

Re: final exam

The final will be 8 questions. One of the questions should be a homework problem.
by Tiffany Dong_4e
Sat Dec 07, 2019 10:34 pm
Forum: Naming
Topic: Numerical Prefixes
Replies: 2
Views: 36

Re: Numerical Prefixes

You use bis, tris, and tetrakis if the compound is polydentate and the regular prefixes in any other instance.
by Tiffany Dong_4e
Sat Dec 07, 2019 10:29 pm
Forum: Bronsted Acids & Bases
Topic: Amphoteric
Replies: 2
Views: 102

Amphoteric

How can you tell if a molecule is amphoteric given its chemical formula?
by Tiffany Dong_4e
Sat Dec 07, 2019 10:26 pm
Forum: Air Pollution & Acid Rain
Topic: acid rain
Replies: 4
Views: 153

Re: acid rain

Know the reactions for carbonic acid and sulfuric acid.
by Tiffany Dong_4e
Sat Dec 07, 2019 10:21 pm
Forum: Biological Examples
Topic: Chemotherapy drugs
Replies: 7
Views: 106

Re: Chemotherapy drugs

Yes, cisplatin is the main compound. I believe we're supposed to know how it functions through its structure as well as possibly knowing how to draw it.
by Tiffany Dong_4e
Sat Dec 07, 2019 10:15 pm
Forum: Bronsted Acids & Bases
Topic: Strong Acids and Bases
Replies: 1
Views: 92

Re: Strong Acids and Bases

This would help because if you memorize the strong acids and bases, you can also determine whichever ones are weak. I would recommend it if you haven't already.
by Tiffany Dong_4e
Sun Dec 01, 2019 4:14 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: pH Scale is broken?
Replies: 6
Views: 89

Re: pH Scale is broken?

Superacids and superbases were briefly mentioned in class, but I believe we don't accommodate for them because they are extreme cases. For the most part, acids and bases should fall within the 0-14 pH scale.
by Tiffany Dong_4e
Sun Dec 01, 2019 4:10 pm
Forum: Student Social/Study Group
Topic: readings
Replies: 13
Views: 292

Re: readings

Professor Lavelle seems to expect us to read the sections corresponding to the current homework of the week. I feel like if you understand all of the homework problems though, you should be fine. Just tailor your studying to your weaknesses and focus on what you feel you don't understand.
by Tiffany Dong_4e
Sun Dec 01, 2019 4:05 pm
Forum: Bronsted Acids & Bases
Topic: Bronsted Base and Acid
Replies: 5
Views: 63

Re: Bronsted Base and Acid

Yes, a Bronsted acid is the proton donor and a Bronsted base is the proton acceptor. This is based on the Bronsted-Lowry definition of acids and bases.
by Tiffany Dong_4e
Sun Dec 01, 2019 4:01 pm
Forum: Lewis Acids & Bases
Topic: Define Acid and Base
Replies: 7
Views: 84

Re: Define Acid and Base

The definition of acid and base depends on which definition you're referring to. Solely considering the Lewis acid and base definition, an acid is an electron acceptor and a base is an electron donor.
by Tiffany Dong_4e
Sat Nov 30, 2019 12:35 am
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Difference between Arrhenius, Bronsted, and Lewis
Replies: 5
Views: 213

Difference between Arrhenius, Bronsted, and Lewis

What are the differences between Arrhenius, Bronsted, and Lewis acids and bases?
by Tiffany Dong_4e
Sun Nov 24, 2019 11:12 pm
Forum: Dipole Moments
Topic: benzene polarity
Replies: 4
Views: 59

Re: benzene polarity

Benzene is nonpolar. Search up the shape and you'll see the symmetrical structure.
by Tiffany Dong_4e
Sun Nov 24, 2019 11:10 pm
Forum: Administrative Questions and Class Announcements
Topic: final exam
Replies: 9
Views: 158

Re: final exam

The number of questions hasn't been given yet, but the length of the final is around 3 hours.
by Tiffany Dong_4e
Sun Nov 24, 2019 10:35 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Drawing molecules
Replies: 7
Views: 114

Re: Drawing molecules

Drawing line structures most likely won't be covered in our class. It's mainly for ochem.
by Tiffany Dong_4e
Sun Nov 24, 2019 10:19 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: AXE Format
Replies: 34
Views: 280

Re: AXE Format

Simply write the letter X or E for a subscript of 1. In addition, if it's a subscript of 0, don't write the letter.
by Tiffany Dong_4e
Sun Nov 24, 2019 10:08 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 17
Views: 365

Re: Cisplatin

It is used to stop cell division for cancer treatment, but it also stops healthy cell division.
by Tiffany Dong_4e
Sun Nov 17, 2019 11:34 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Resonance and VSEPR
Replies: 9
Views: 102

Re: Resonance and VSEPR

They aren't. VSEPR is only determined by the regions of electron density and amount of bonding/lone pairs.
by Tiffany Dong_4e
Sun Nov 17, 2019 11:32 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizable vs polarizing power
Replies: 5
Views: 186

Re: Polarizable vs polarizing power

These terms are used to describe the characteristics of ions. Polarizability is generally associated with anions and polarizing power with cations, but this isn't a steadfast rule by any means.
by Tiffany Dong_4e
Sun Nov 17, 2019 11:26 pm
Forum: Bond Lengths & Energies
Topic: Test 2 Topics
Replies: 40
Views: 841

Re: Test 2 Topics

The topics we've covered so far since the midterm are VSEPR, bond angles, and intermolecular forces. We will also be tested on what we learn Monday which will include pi and sigma bonds along with other material.
by Tiffany Dong_4e
Sun Nov 17, 2019 11:22 pm
Forum: Trends in The Periodic Table
Topic: electron affinity
Replies: 7
Views: 202

Re: electron affinity

Electron affinity has a similar trend to electronegativity and ionization energy. (it increases going up and to the right)
by Tiffany Dong_4e
Sun Nov 17, 2019 11:21 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Naming the Molecular Shapes
Replies: 7
Views: 115

Re: Naming the Molecular Shapes

Visualizing the shapes in my head helps me remember them because the names of the shapes are based off of how they're formed in real life i.e. trigonal planar is a flat triangle or seesaw is shaped like a seesaw.
by Tiffany Dong_4e
Mon Nov 11, 2019 10:34 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: 6
Views: 54

Re: london forces

Yes, all molecules have london dispersion forces. However, the more electrons a molecule has, the stronger the forces are.
by Tiffany Dong_4e
Mon Nov 11, 2019 10:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: central atoms
Replies: 7
Views: 76

Re: central atoms

The central atom is typically determined by whichever atom has the lowest electronegativity. Aside from this, the atom which is alone or has the lowest quantity is usually in the center.
by Tiffany Dong_4e
Mon Nov 11, 2019 10:24 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal charge
Replies: 16
Views: 212

Re: Formal charge

Getting close to 0 is ideal, but the "next best" option would be giving a more electronegative atom like oxygen a negative charge.
by Tiffany Dong_4e
Mon Nov 11, 2019 10:23 pm
Forum: Lewis Structures
Topic: Test Questions regarding Electronegativity
Replies: 2
Views: 46

Re: Test Questions regarding Electronegativity

I believe so because we used a chart to determine electronegativity difference in lecture. Generally, anything we need should be provided for us on the test.
by Tiffany Dong_4e
Mon Nov 11, 2019 10:21 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizing Power
Replies: 6
Views: 103

Re: Polarizing Power

A cation's ability to distort an anion's electron cloud is polarizing power. Polarizability is the tendency of a cation to be affected by an anion's polarizing power.
by Tiffany Dong_4e
Sun Nov 03, 2019 8:39 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 4s or 3d first?
Replies: 14
Views: 360

Re: 4s or 3d first?

Lavelle wants us to write 3d before 4s, but I in general it isn't incorrect to write 4s before 3d. I think you should maintain class expectations for the test though.
by Tiffany Dong_4e
Sun Nov 03, 2019 8:36 pm
Forum: *Black Body Radiation
Topic: Info for Midterm
Replies: 10
Views: 314

Re: Info for Midterm

He mentioned this briefly, but stated it will not be tested in this class.
by Tiffany Dong_4e
Sun Nov 03, 2019 8:32 pm
Forum: Resonance Structures
Topic: Do we always need to draw resonance?
Replies: 1
Views: 37

Do we always need to draw resonance?

If a molecule has resonance structures, but they are not explicitly asked for in the problem, do we still need to draw them?
by Tiffany Dong_4e
Sun Nov 03, 2019 8:31 pm
Forum: Resonance Structures
Topic: Resonance Structures
Replies: 1
Views: 36

Resonance Structures

How do we determine if a molecule has resonance structures?
by Tiffany Dong_4e
Sun Nov 03, 2019 8:13 pm
Forum: Octet Exceptions
Topic: Elements with Exceptions to Octet Rule
Replies: 1
Views: 34

Elements with Exceptions to Octet Rule

Which elements have exceptions to the octet rule? i.e. Phosphorous which can have an expanded octet or Boron which doesn't need a full octet
by Tiffany Dong_4e
Sun Oct 27, 2019 8:57 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent Bonds
Replies: 14
Views: 167

Re: Covalent Bonds

Yes, it's only between nonmetals. If other metals were involved, it would probably be a different type of bond.
by Tiffany Dong_4e
Sun Oct 27, 2019 8:47 pm
Forum: Resonance Structures
Topic: Resonance Structures
Replies: 3
Views: 59

Re: Resonance Structures

Resonant structures allow for greater accuracy when modeling certain molecules because they show us that those molecules have delocalized electrons which can move around. You don't "need" to move the bond, but it is good to know that the bond can move.
by Tiffany Dong_4e
Sun Oct 27, 2019 8:40 pm
Forum: Bond Lengths & Energies
Topic: bond lengths for single or double bonds
Replies: 7
Views: 64

Re: bond lengths for single or double bonds

The stronger the bond, the shorter the bond length, so double bonds will be shorter than single bonds.
by Tiffany Dong_4e
Sun Oct 27, 2019 6:03 pm
Forum: Properties of Electrons
Topic: Determining Number of Valence Electrons
Replies: 2
Views: 48

Determining Number of Valence Electrons

Are we expected to know the number of valence electrons in transition metals? It was a homework problem, so I wanted to make sure. The problem stated to identify the number of valence electrons (including d electrons) in magnesium. If we are expected to know this, how would we determine the number?
by Tiffany Dong_4e
Sun Oct 27, 2019 1:26 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration Special Cases
Replies: 6
Views: 157

Electron Configuration Special Cases

Aside from chromium and copper, are there any other elements that have "exceptions" in electron configuration?
by Tiffany Dong_4e
Mon Oct 21, 2019 2:27 am
Forum: Trends in The Periodic Table
Topic: Difference between electron affinity and electronegativity?
Replies: 3
Views: 35

Re: Difference between electron affinity and electronegativity?

Electron affinity is the likelihood of an atom gaining an electron, while electronegativity is the tendency of an atom to attract electrons.
by Tiffany Dong_4e
Mon Oct 21, 2019 2:04 am
Forum: Photoelectric Effect
Topic: Threshold Energy
Replies: 7
Views: 124

Re: Threshold Energy

I'm also confused how an electron is "ejected" with no kinetic energy. Could someone clarify further?
by Tiffany Dong_4e
Mon Oct 21, 2019 1:15 am
Forum: Properties of Light
Topic: Balmer and Lyman Series
Replies: 5
Views: 94

Re: Balmer and Lyman Series

The electron moving from n1 to n2 is the process of it being excited. The Lyman and Balmer series describe the electron as it is falling back down to lower energy levels from its excited state.
by Tiffany Dong_4e
Mon Oct 21, 2019 12:55 am
Forum: Administrative Questions and Class Announcements
Topic: Periodic Table on the Test
Replies: 7
Views: 115

Re: Periodic Table on the Test

You're provided a periodic table, along with an equation sheet, so I believe you should use those so that your answers will be more accurate. (:
by Tiffany Dong_4e
Mon Oct 21, 2019 12:42 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: What's the right equation?
Replies: 7
Views: 107

Re: What's the right equation?

If you're referring to the Heisenberg Uncertainty Equation, it should be the first one.
by Tiffany Dong_4e
Mon Oct 14, 2019 9:22 am
Forum: Properties of Light
Topic: Wave Frequency
Replies: 9
Views: 115

Re: Wave Frequency

I also believe it is the amount of energy per photon because photons are essentially discrete packets of energy in the form of waves.
by Tiffany Dong_4e
Mon Oct 14, 2019 9:12 am
Forum: Properties of Light
Topic: Quantum Levels
Replies: 1
Views: 34

Re: Quantum Levels

If you're asking whether or not a quanta can have a value other than a whole number then this is not possible. They can, however, have values that continue to infinity as long as they're whole.
by Tiffany Dong_4e
Mon Oct 14, 2019 8:44 am
Forum: Properties of Light
Topic: Memorizing Values for Tests
Replies: 3
Views: 26

Re: Memorizing Values for Tests

The values will be provided for you on the formula sheet, so you don't have to memorize them. However, I would try to memorize ones that reoccur often like Planck's constant.
by Tiffany Dong_4e
Mon Oct 14, 2019 8:34 am
Forum: Student Social/Study Group
Topic: Best Sessions
Replies: 12
Views: 179

Re: Best Sessions

The step-up sessions help me a lot because they go at a slower pace. In workshops, you're expected to know the material.
by Tiffany Dong_4e
Sun Oct 06, 2019 11:56 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Theoretical vs. Actual Yield
Replies: 38
Views: 3399

Re: Theoretical vs. Actual Yield

The actual yield is generally not equal to the theoretical yield because of impurities during experimentation or other factors such as solution staying on the sides of the beaker. In order for the actual yield to equal the theoretical yield, the experiment would need to be executed perfectly.
by Tiffany Dong_4e
Sun Oct 06, 2019 11:49 pm
Forum: Balancing Chemical Reactions
Topic: Naming/Polyatomic ions
Replies: 4
Views: 64

Re: Naming/Polyatomic ions

I was told by my TA that it would definitely be useful to memorize the polyatomic ions, but I don't think they'll be particularly relevant to the test.
by Tiffany Dong_4e
Sun Oct 06, 2019 11:46 pm
Forum: Limiting Reactant Calculations
Topic: Question about Calculating Limiting Reactants
Replies: 5
Views: 77

Question about Calculating Limiting Reactants

Are you allowed to simply calculate the moles of each reactant and then compare them to find the limiting reagent?
by Tiffany Dong_4e
Sun Oct 06, 2019 3:18 pm
Forum: Significant Figures
Topic: Inaccurate Answer
Replies: 4
Views: 92

Inaccurate Answer

I don't know what my problem is, but I seem to always be slightly off the answer. Could I get some advice? For example, I'll calculate the molar mass of C6H12O6 and get 180.14 g/mol rather than 180.15 g/mol like the book says. The way I've been doing it is I keep the values of the atomic masses the ...
by Tiffany Dong_4e
Sat Oct 05, 2019 6:15 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Atoms, Molecules, and Formula Units
Replies: 4
Views: 136

Atoms, Molecules, and Formula Units

How is it possible that Avogadro's Constant can be used to find atoms, molecules, and formula units? Does whichever item you're finding depend on the substance involved in the problem?
by Tiffany Dong_4e
Fri Oct 04, 2019 12:40 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 133
Views: 33562

Re: Final Jitters

I think many people experience test anxiety and that's okay! I usually cope by doing something I enjoy before a test such as playing piano or reading a book. I'm still a first year though so my experience is also limited. I think the best strategy is to simply be prepared. If you feel ready, that sh...

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