## Search found 50 matches

Wed Dec 04, 2019 1:01 am
Forum: Air Pollution & Acid Rain
Topic: What do we need to know?
Replies: 4
Views: 142

### Re: What do we need to know?

It is better to know the relation but it won't be directly asked on the final, I believe. Because it is cumulative, any information is fair deal if shared in lectures or discussion sections, so have a heads up.
Wed Dec 04, 2019 12:59 am
Forum: Calculating the pH of Salt Solutions
Topic: Anion Exceptions
Replies: 3
Views: 45

### Re: Anion Exceptions

The two compounds are exceptions because they can act as acid and give off H while most anions are not able to due to their charges.
Wed Dec 04, 2019 12:57 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: How do we write the equation to find the pH of a SA and WB
Replies: 1
Views: 35

### Re: How do we write the equation to find the pH of a SA and WB

We would have 2 HCl and the equation would look like: 2HCl+CaO-->CaCl2+H2O (hopefully this is right) We won't be using the ice table in 14a because all the problems will involve strong acids that completely disassociate so finding pH would be using the same amount given to the strong acid. We will d...
Wed Dec 04, 2019 12:50 am
Forum: Calculating the pH of Salt Solutions
Topic: pH Sig Figs
Replies: 4
Views: 72

### Re: pH Sig Figs

the zero acts as a placeholder after the decimal so it is counted as a part of the sig fig.
Wed Dec 04, 2019 12:47 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Basic or Acidic
Replies: 2
Views: 54

### Re: Basic or Acidic

If no hydrogens are available, you look at the compounds using the definitions of Lewis base/acid whether they are accepting electrons or donating electrons.
Tue Nov 26, 2019 4:37 pm
Forum: Bronsted Acids & Bases
Topic: Bronsted Acids and Bases
Replies: 6
Views: 70

### Re: Bronsted Acids and Bases

Know the definitions of the bronzed acids and bases because we just need to know how to distinguish them from the definitions of Arrhenius or Lewis. We will learn more about them in 14b.
Tue Nov 26, 2019 4:36 pm
Forum: Naming
Topic: Final Exam
Replies: 3
Views: 55

### Re: Final Exam

The chart provided by Dr. Lavelle is the safest bet in memorizing the way to name the coordination compounds that he taught us in class.
Tue Nov 26, 2019 4:33 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: brackets
Replies: 13
Views: 152

### Re: brackets

brackets are the symbol for the coordination sphere that has all the compound that are coordinating inside the sphere.
Tue Nov 26, 2019 4:30 pm
Forum: Conjugate Acids & Bases
Topic: Cojugate Acids and Bases
Replies: 10
Views: 558

### Re: Cojugate Acids and Bases

the acid and bases on the reactant side, when it goes into the product side, the base that accepts the H+ becomes the conjugate acid while the acid that loses H+ becomes conjugate base.
Tue Nov 26, 2019 4:28 pm
Forum: Conjugate Acids & Bases
Topic: Acids and Bases
Replies: 10
Views: 133

### Re: Acids and Bases

every reaction involving acids and/or bases have the equilibrium arrows but the strong acids and bases completely dissociate and do not go to its original form so the equilibrium arrow does not work. For weak acids and bases, the equilibrium arrows are more emphasized as they can reverse back to its...
Tue Nov 19, 2019 12:34 am
Forum: Administrative Questions and Class Announcements
Topic: Test 2
Replies: 7
Views: 96

### Re: Test 2

Either will work as long as you use the word for right shape. In class, Professor uses bent so you can go with bent if it is easier for you.
Tue Nov 19, 2019 12:31 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Hydrogen bonding
Replies: 2
Views: 54

### Re: Hydrogen bonding

Hydrogen bonding is a bond between. molecule with N, O, or F with H. Water can have upto 4 sites for H bonds because water has two H bonded and two lone pairs on O to which two more can bond, creating H bonding.
Tue Nov 19, 2019 12:17 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Sigma and Pi Bonds
Replies: 18
Views: 334

### Re: Sigma and Pi Bonds

Yes we need the definition and how they are present in the bonds. In the triple bond, there would be 1 sigma and 2 pi bonds most of the time.
Tue Nov 19, 2019 12:14 am
Forum: Determining Molecular Shape (VSEPR)
Topic: seesaw
Replies: 5
Views: 80

### Re: seesaw

Due to the repulsion of the lone pairs, they should be less than 90 and 120.
Tue Nov 19, 2019 12:13 am
Forum: Determining Molecular Shape (VSEPR)
Topic: AXE formula
Replies: 9
Views: 85

### Re: AXE formula

A is the central atom and AX2E is considered as bent shape.
Wed Nov 13, 2019 11:26 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: hydrogen bonding
Replies: 3
Views: 28

### Re: hydrogen bonding

Hydrogen bonding occurs with H being covalently bonded to any of the N,O,F elements as it is the intermolecular force felt by the H with the N,O,F and another lone pair of H with N,O,F bonded.
Wed Nov 13, 2019 11:23 am
Forum: Dipole Moments
Topic: Intermolecular Forces
Replies: 6
Views: 63

### Re: Intermolecular Forces

CHI3 does due to the size being greater than CHF3 so the boiling point increases for I.
Wed Nov 13, 2019 11:22 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Molecule Size and Melting Points
Replies: 6
Views: 59

### Re: Molecule Size and Melting Points

When the molecules has similar structures, we look at the size to see which one has a higher boiling point. As the size increases, the boiling point increases as well.
Wed Nov 13, 2019 11:21 am
Forum: Bond Lengths & Energies
Topic: Homework for week 7
Replies: 5
Views: 66

### Re: Homework for week 7

you can do the hw from the chemical bonds outline if you haven't finished doing so, and also go to the next outline. Just has to be material covered in class as of now.
Wed Nov 13, 2019 11:19 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Covalent bonding
Replies: 5
Views: 54

### Re: Covalent bonding

Covalent bonding is considered as intramolecular force as it holds atoms together in a molecule but intermolecular forces are forces of attraction or repulsion between molecules.
Tue Nov 05, 2019 10:58 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Midterm
Replies: 6
Views: 203

### Re: Midterm

we don't have to memorize the specific experiments but the concepts may come up in the tests, so maybe going over them might be helpful.
Tue Nov 05, 2019 10:52 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Midterm
Replies: 3
Views: 181

### Re: Midterm

We don't have to memorize them, they are just references to better understand the orbitals.
Tue Nov 05, 2019 10:44 pm
Forum: SI Units, Unit Conversions
Topic: HELP WITH UNITS
Replies: 9
Views: 464

### Re: HELP WITH UNITS

you should follow what the question wants as the final result, most of the time it will ask in standard units so you will be fine.
Tue Nov 05, 2019 2:33 pm
Forum: Lewis Structures
Topic: Central Atom
Replies: 3
Views: 56

### Re: Central Atom

most of the times, the central atom is always the one with the lowest ionization energy. In this case, even though Br sounds like a perfect match, if you look up the ionization energy of the elements, carbon is slightly lower than bromine.
Tue Nov 05, 2019 2:31 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 4s or 3d first?
Replies: 14
Views: 385

### Re: 4s or 3d first?

we write 3d before 4s due to the location of the electrons on that orbital and how they react with losing/gaining electrons.
Thu Oct 31, 2019 3:29 pm
Forum: Trends in The Periodic Table
Topic: blocks
Replies: 13
Views: 158

### Re: blocks

It is easier to have a physical copy of periodic table and highlight the different blocks on there to make life easier. It has helped me personally in memorizing the orbitals and their characteristics.
Thu Oct 31, 2019 3:26 pm
Forum: Lewis Structures
Topic: valence electrons
Replies: 4
Views: 93

### Re: valence electrons

Valence electrons increase by 1 as you go from left to right on the periodic table. So it goes from 1 such as Li to 8 such as Ne.
Thu Oct 31, 2019 3:23 pm
Forum: Lewis Structures
Topic: valence electrons of nonmetals
Replies: 3
Views: 37

### Re: valence electrons of nonmetals

The valence electrons for nonmetals are mostly 2 due to the charge of the s orbital being more than the d orbital and those 2 electrons are engaged in any bonds created with the certain nonmetal.
Thu Oct 31, 2019 3:21 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge
Replies: 5
Views: 65

### Re: Formal Charge

it does not always show up where the middle element has a formal charge of 0 but it is better if it does. To look for the resonance of the molecule and to find the most stable lewis structure, you have to find the formal charge of the elements in the molecule to see how the charge is distributed.
Thu Oct 31, 2019 3:18 pm
Forum: Ionic & Covalent Bonds
Topic: Valence Electrons?
Replies: 15
Views: 211

### Re: Valence Electrons?

Cl has 7 valence electrons, the valence electrons go in order of the row so it increases by 1 as you go from left to right. The noble gases are stable as they have full 8 valence electrons and do not involve in the bonds associated with the other elements.
Tue Oct 22, 2019 1:33 am
Forum: Quantum Numbers and The H-Atom
Topic: f- orbitals?
Replies: 7
Views: 81

### Re: f- orbitals?

Except the homework problems, we won't be really tested on the f orbital on our midterms and finals. It comes up as the textbook has problems for all the orbitals but we just give more attention to s, p, and d orbitals.
Tue Oct 22, 2019 1:31 am
Forum: Administrative Questions and Class Announcements
Topic: Week 4 homework problems
Replies: 5
Views: 67

### Re: Week 4 homework problems

We are still under the quantum world but under section 1D so you can do the problems under 1D for this week.
Tue Oct 22, 2019 1:30 am
Forum: Trends in The Periodic Table
Topic: Metals, Nonmetals, Metalloids
Replies: 5
Views: 89

### Re: Metals, Nonmetals, Metalloids

I do not think you have to memorize every element under the categories but a quick way to memorize the placements of the elements is by highlighting the parts on a physical periodic table, so you see which areas are under metal, metalloids, and nonmetal. Draw the diagonal line on the right side of t...
Tue Oct 22, 2019 1:25 am
Forum: Trends in The Periodic Table
Topic: Homework #4
Replies: 5
Views: 78

### Re: Homework #4

You just do the homework under the quantum world section but under 1D as it specifically goes over the topics discussed in class as of now.
Tue Oct 22, 2019 1:23 am
Forum: Ionic & Covalent Bonds
Topic: Week 4 Homework
Replies: 9
Views: 153

### Re: Week 4 Homework

This week we still do the homework under the quantum world, just go over the 1D section as it talks about all the topics we covered and do homework under the assigned problems of 1D.
Thu Oct 17, 2019 2:20 am
Forum: Significant Figures
Topic: Tests and Significant Figures
Replies: 6
Views: 217

### Re: Tests and Significant Figures

If a problem has several amounts given with different significant figures, it is best to at least have the lowest significant figure given by the problems. To be sure, ask your TA as significant figures are essential for points on tests.
Thu Oct 17, 2019 2:18 am
Forum: Properties of Light
Topic: Constant for Speed of Light
Replies: 14
Views: 219

### Re: Constant for Speed of Light

It is best to use 2.99*10^8 as it is more accurate but make sure you ask your TA about it because when using it, you have to be careful about significant figures of the end result.
Thu Oct 17, 2019 2:16 am
Forum: General Science Questions
Topic: Pre-Calc and Calculus
Replies: 3
Views: 63

### Re: Pre-Calc and Calculus

The math done in this class is pretty straight forward if you follow the formulas given in the problems and use the formula sheet. I do not think knowing calculus will advance anything as Professor Lavelle goes through each type of math used in lectures. You should be fine.
Thu Oct 17, 2019 2:14 am
Forum: Properties of Electrons
Topic: electron mass
Replies: 8
Views: 102

### Re: electron mass

The mass is given in the sheet but for your best, just memorize the mass so it gets easier when significant figures are at stake.
Thu Oct 17, 2019 2:13 am
Forum: Quantum Numbers and The H-Atom
Topic: spin up and spin down
Replies: 7
Views: 72

### Re: spin up and spin down

We just need to know what the signs mean in case of the electron spinning upwards or downwards, not putting an emphasis on the charge of the +1/2 or -1/2. They act as placeholders when looking for the orbitals using the numbers in parenthesis such as (2, 1, 0, 1/2).
Thu Oct 10, 2019 5:03 pm
Forum: Significant Figures
Topic: Sig Figs only for Decimal Points vs for all integers in the Answer
Replies: 5
Views: 107

### Re: Sig Figs only for Decimal Points vs for all integers in the Answer

If any problems have multiple numbers with different amounts of sig. figs., write your answer in the lowest number of sig. figs. Just talk to your TA about it more because they will let you know how the sig. figs. are looked at and graded.
Thu Oct 10, 2019 4:56 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Chemical Reactions
Replies: 20
Views: 522

### Re: Balancing Chemical Reactions

It will be easier to see which element already has the largest amount on the reactant side and see the proportion of the same element on the product side. One by one, plug in the coefficients. If you have to, rewrite the new balanced equation and recheck your coefficients to see if both sides have s...
Thu Oct 10, 2019 4:52 pm
Forum: Significant Figures
Topic: How many significant figures are in 7.00 x 10^2?
Replies: 25
Views: 518

### Re: How many significant figures are in 7.00 x 10^2?

7.00x10^2 and 700 are the same numbers but different notation. So the significant figures for both are 3 as the sig. figures are based on the amount of integers, including 0 after a number or decimal.
Thu Oct 10, 2019 4:49 pm
Forum: Limiting Reactant Calculations
Topic: general questions
Replies: 11
Views: 486

### Re: general questions

Out of the reactants given, finding the limiting reactant helps to find the accurate amount of moles for the products and which reactant is in excess. Using the reactant with is limited, the moles can be calculated and give out the moles of the products as well as the amount of the other reactants w...
Thu Oct 10, 2019 4:46 pm
Forum: Student Social/Study Group
Topic: Pen or Pencil for Homework Problems?
Replies: 8
Views: 140

### Re: Pen or Pencil for Homework Problems?

No it does not matter, as long as you show all your work and label your homework with your name, UID, and discussion section.
Wed Oct 02, 2019 6:05 pm
Forum: Molarity, Solutions, Dilutions
Topic: General Rounding Question
Replies: 9
Views: 84

### Re: General Rounding Question

For using the molar mass of any element, you would usually go for 2-3 sig. figures but when you write your answer, it must match up to the correct amount of sig. figures given in the question. For something like Hydrogen, the amount mostly correlates to 1g/mol.
Wed Oct 02, 2019 5:56 pm
Forum: SI Units, Unit Conversions
Topic: Homework for Week 1
Replies: 16
Views: 380

### Re: Homework for Week 1

I believe we get to do five questions from the textbook which is due at the beginning of lecture this Friday, Oct. 4. The remaining hw, including the quantum problems, are due in your discussion class as he will go over the topic by your next lecture class.
Wed Oct 02, 2019 5:50 pm
Forum: Ionic & Covalent Bonds
Topic: Ionic vs Covalent
Replies: 32
Views: 11825

### Re: Ionic vs Covalent

Ionic bonds are way stronger than covalent unless you look for the hydrogen bonding with fluorine, nitrogen, and oxygen. It depends on the interactions between the atoms that causes the differences.
Wed Oct 02, 2019 5:48 pm
Forum: SI Units, Unit Conversions
Replies: 22
Views: 398

### Re: Question about Showing Work

As each step may carry points that we might to know of, it is of your best interest to show all the steps. It may be tedious but you will be glad once they are graded. It goes for both homework and classwork activities.
Wed Oct 02, 2019 5:45 pm
Forum: Empirical & Molecular Formulas
Topic: QUESTION F3
Replies: 3
Views: 153

### Re: QUESTION F3

nitric acid falls under the table of memorizing specific ions and their acid/base compounds. Even if you do not perform the calculations for finding empirical formula, nitric acid is derived from the the combination of N and O, for which we have to memorize the ions. Then, you simply add H+ as it is...