## Search found 36 matches

Thu Jun 14, 2018 1:19 pm
Forum: Air Pollution & Acid Rain
Topic: Acid Rain
Replies: 15
Views: 1486

### Re: Acid Rain

Acidic rain forms from sulfur dioxide and nitrogen are released in to the air (as from coal power plants) and interact with water or oxygen.
Thu Jun 14, 2018 1:08 am
Forum: Molarity, Solutions, Dilutions
Topic: French Toast #27a
Replies: 1
Views: 226

### Re: French Toast #27a

For part A, use the equation m1v1=m2v2. So 1.50*v1=(.550m)(210mL), v1=77mL.

For part B, use pH+pOH=14-(-log[OH-]), so pH=14.04.
Thu Jun 14, 2018 1:03 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: strong/weak acids (from review worksheet)
Replies: 1
Views: 277

### Re: strong/weak acids (from review worksheet)

In the UA session, she was saying that it's like "spotting the difference" between them. So you would compare the electronegativity of the right side of the 4 since the left are similar in 1, 2, and 3.
Wed Jun 13, 2018 10:40 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: hw 4.21d
Replies: 2
Views: 412

### hw 4.21d

Hi, Why is the answer for 4.21d a trigonal pyramidal with 107 degrees? The question asked for the lewis structure and angle of N2H4. I was wondering why the bond angle wouldn't be the same as part a in the same question for C2H4 that has a bond angle of 120 degrees. Also, why couldn't a double or tr...
Sun Jun 10, 2018 11:14 pm
Forum: General Science Questions
Topic: Final [ENDORSED]
Replies: 10
Views: 761

### Re: Final[ENDORSED]

Oh no, sorry I mean just one midterm.
Sun Jun 10, 2018 10:42 pm
Forum: Amphoteric Compounds
Topic: Amphoteric and amphiprotic
Replies: 6
Views: 782

### Re: Amphoteric and amphiprotic

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH. To be considered amphiprotic, does it have to act as a proton donor and acceptor, or only one of the two? Yes, I ...
Sun Jun 10, 2018 10:37 pm
Forum: Amphoteric Compounds
Topic: Amphoteric and amphiprotic
Replies: 6
Views: 782

### Re: Amphoteric and amphiprotic

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH. It would also be helpful to know polyprotic which has more than one proton to donate ( if it is an acid) or accep...
Sun Jun 10, 2018 10:35 pm
Forum: Amphoteric Compounds
Topic: Amphoteric and amphiprotic
Replies: 6
Views: 782

### Re: Amphoteric and amphiprotic

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH.
Sun Jun 10, 2018 10:14 pm
Forum: Student Social/Study Group
Topic: Past Final Exams
Replies: 6
Views: 470

### Past Final Exams

Hi, Does anyone have access to past final exams, tests, or midterms from past 14a course readers? If so, does anyone mind emailing me? ak9ee@g.ucla.edu
Sun Jun 10, 2018 10:02 pm
Forum: General Science Questions
Topic: Final [ENDORSED]
Replies: 10
Views: 761

### Re: Final[ENDORSED]

A TA told me that it would be similar to the set up from midterm 1 and 2. So 8 questions total. 4 questions may be from either midterm 1 or 2, and the other 4 will be new material. But each question will have multiple parts. But I'm not sure how accurate this is.
Sun Jun 10, 2018 9:57 pm
Forum: Lewis Acids & Bases
Topic: Determining Acid Strength
Replies: 6
Views: 540

### Re: Determining Acid Strength

Alejandro Salazar 1D wrote:I would recommend memorizing the 7 common strong acids, which are HCI, HBr, HI, HNO3, HCIO3, HCIO4, H2SO4

Are those acids already ranked from strongest to weakest? For example, HCl > HBr > HI ......?
Sun Jun 10, 2018 9:52 pm
Forum: Administrative Questions and Class Announcements
Topic: Saying Thank You to Dr. Lavelle
Replies: 291
Views: 136060

### Re: Saying Thank You to Dr. Lavelle

Thank you Dr. Lavelle!

As a first year at UCLA, you made me feel comfortable taking 14A this quarter with no prior chemistry background from high school!
Sun Jun 10, 2018 8:26 pm
Forum: Lewis Acids & Bases
Topic: Determining Acid Strength
Replies: 6
Views: 540

### Determining Acid Strength

How would i determine the differences in strengths of acids? or how would i rank the acids? Would i determine the strength based on which is most acidic and which is the most electronegative?

...or does anyone have any recommendations to do this?
Sun Jun 10, 2018 8:08 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: metal oxides
Replies: 1
Views: 298

### metal oxides

Are metal oxides bases and nonmetal oxides acids?
Sun Jun 03, 2018 11:49 pm
Forum: Sigma & Pi Bonds
Topic: Difference between Bonds [ENDORSED]
Replies: 7
Views: 654

### Re: Difference between Bonds[ENDORSED]

What is an example of how we may be given a test question for sigma and pi bonds?
Sun Jun 03, 2018 11:48 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR shape and bond angles
Replies: 5
Views: 373

### Re: VSEPR shape and bond angles

Okay, thank you! I believe I understand how to determine the difference now.
Thu May 31, 2018 1:46 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR shape and bond angles
Replies: 5
Views: 373

### VSEPR shape and bond angles

Hi, I read that molecules with the same VSEPR formula have the same shape, but differ in bond angle. How would I determine the difference between the bond angles in different molecules with the same shape and VSEPR formula? Also how would I be able to recognize the exceptions to this? In the book it...
Sun May 27, 2018 8:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecules with lone pairs
Replies: 1
Views: 135

### Molecules with lone pairs

If we were to encounter a molecule with a single lone pair electron on the central atom, how would we began to determine the shape?
Sun May 27, 2018 8:04 pm
Forum: Bond Lengths & Energies
Topic: Bond Strength
Replies: 5
Views: 459

### Re: Bond Strength

For the length of bond the order is: triple < double < single.
Sun May 27, 2018 7:54 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR and Lewis
Replies: 4
Views: 254

### Re: VSEPR and Lewis

@Ashley, because single bonds and multiple bonds are treated as equivalent in the VSEPR model, it doesn't matter which of the Lewis Structures contributing to a resonance structure we consider.
Sun May 20, 2018 11:35 pm
Forum: Lewis Structures
Topic: Different ways to write the lewis structure?
Replies: 6
Views: 420

### Re: Different ways to write the lewis structure?

I think they're both correct, but they're usually written as equally distributed.
Sun May 20, 2018 11:31 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Stable Lewis structures
Replies: 4
Views: 280

### Re: Stable Lewis structures

For more on determining stable lewis structures, refer to example 3.6 in the text book. It includes an example, and indicates the equation with all steps.
Sun May 20, 2018 11:29 pm
Forum: Ionic & Covalent Bonds
Topic: Test 3
Replies: 2
Views: 199

### Re: Test 3

For test 3, should we identify if a covalent bond is polar or non polar?
Sat May 05, 2018 11:02 pm
Forum: Ionic & Covalent Bonds
Topic: Midterm Topics [ENDORSED]
Replies: 33
Views: 2748

### Re: Midterm Topics[ENDORSED]

Does anyone know if we need to know aufbau, hund, and pauli principles?
Sat May 05, 2018 11:01 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: homework 2.43 part e [ENDORSED]
Replies: 8
Views: 497

### Re: homework 2.43 part e[ENDORSED]

the answer is 4f^14 because you need to include the configuration for the f-block, so not including La, there would be 14 e- total.
Sun Apr 29, 2018 11:13 pm
Forum: Trends in The Periodic Table
Topic: s, p, d, f
Replies: 16
Views: 3462

### Re: s, p, d, f

What type of midterm questions/practice problems are possible for s, p, d, f?
Sun Apr 29, 2018 11:06 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Balmer and Lyman Series
Replies: 9
Views: 899

### Re: Balmer and Lyman Series

For the upcoming midterm, do we need to be familiar with any other series besides balmer and lyman series?
Sun Apr 29, 2018 11:04 pm
Forum: Administrative Questions and Class Announcements
Topic: Study Guide for Midterm? [ENDORSED]
Replies: 3
Views: 344

### Re: Study Guide for Midterm?[ENDORSED]

Will there be a guide or list of chem topics that we need to focus on for the upcoming midterm?
Mon Apr 23, 2018 12:00 am
Forum: Ideal Gases
Replies: 153
Views: 105485

Has anyone found any other resources outside of class that is useful for preparing for the test? Like any practice exam/test problems?
Sun Apr 22, 2018 11:56 pm
Forum: SI Units, Unit Conversions
Replies: 9
Views: 730

What is a good way to determine when to used avogadro's #?
Sun Apr 22, 2018 11:55 pm
Forum: Properties of Light
Topic: Memorizing formulas test 2
Replies: 16
Views: 900

### Re: Memorizing formulas test 2

So we still need to memorize the units of the equations?
Mon Apr 16, 2018 12:38 am
Forum: Properties of Light
Topic: Speed of light constant
Replies: 5
Views: 308

### Re: Speed of light constant

Do we need to memorize the speed of light in different conditions for the exam?
Mon Apr 16, 2018 12:27 am
Forum: General Science Questions
Topic: Rusty on High School Chem [ENDORSED]
Replies: 200
Views: 141267

### Re: Rusty on High School Chem[ENDORSED]

I have not taken Chemistry since high school and the first test for outline 1 was difficult. Is there any practice problems that are more similar to test questions or are more difficult than the weekly homework problems?
Mon Apr 16, 2018 12:09 am
Forum: Student Social/Study Group
Topic: Study Group
Replies: 8
Views: 626

### Re: Study Group

Does anybody have a groupme link for the study group?
Mon Apr 16, 2018 12:01 am
Forum: Properties of Light
Topic: Homework? [ENDORSED]
Replies: 10
Views: 554

### Re: Homework?[ENDORSED]

If we have our discussion towards to beginning of the week, are we able to answer questions from outline 1 instead of outline 2? I have discussion on Tuesday and I feel like we haven't went over new materials on outline 2.
Sun Apr 15, 2018 11:59 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Accuracy vs Precision
Replies: 23
Views: 1412

### Re: Accuracy vs Precision

According to lecture precision indicates how close measurements are to one another while accuracy is the accuracy to the true value.