Search found 57 matches

by Isabel_Eslabon_2G
Sun Jan 10, 2021 10:49 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q>K
Replies: 10
Views: 47

Re: Q>K

I think one example of when Q > K is when the reaction is not quite at equilibrium yet so there are still products that are forming reactants. Because K & Q = [Products]/[Reactants], if Q > K, then there are more products that are still forming those reactants. This can also occur if more produc...
by Isabel_Eslabon_2G
Sun Jan 10, 2021 10:46 am
Forum: Administrative Questions and Class Announcements
Topic: 14B Midterm Content
Replies: 4
Views: 29

14B Midterm Content

Hi. For our final & midterms, are we only being tested on content that we learned in 14B or also 14A? I know that some foundation from 14A will be utilized when understanding certain concepts from 14B, but for example, will topics related to quantum mechanics be on those exams? I don't remember ...
by Isabel_Eslabon_2G
Sun Jan 10, 2021 10:41 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Equilibrium constant between 10^-3 and 10^3
Replies: 6
Views: 13

Re: Equilibrium constant between 10^-3 and 10^3

I think Lavelle said that if 10^-3 < K < 10^3 (intermediate values of K), then neither reactants nor products are strongly favored in that reaction (from the lecture on 1/6).
by Isabel_Eslabon_2G
Sun Jan 10, 2021 10:39 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs Q
Replies: 7
Views: 19

Re: K vs Q

Hello. I'm pretty sure both K & Q are found by dividing product concentrations (to the power of their coefficients) by the reactant concentrations (to the power of their coefficients). The difference is that K uses equilibrium concentrations. When you are given concentrations of reactants & ...
by Isabel_Eslabon_2G
Mon Jan 04, 2021 4:20 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Sapling Week 1 Problem #1
Replies: 4
Views: 39

Sapling Week 1 Problem #1

The question is: "Select all of the true statements regarding chemical equilibrium:" Two of the options are: 1. "The concentrations of the reactants and products are equal" 2. "The concentrations of the reactants and products remain constant" #2 is true and #1 is false....
by Isabel_Eslabon_2G
Wed Dec 16, 2020 6:41 pm
Forum: General Science Questions
Topic: final timing
Replies: 24
Views: 100

Re: final timing

I usually finish exams (especially multiple choice ones) with a moderate amount of time to spare, but this exam went by pretty fast. But I kind of expected it because it was a final and braced myself for the possibility that I may not finish. Personally, the questions with finding empirical formula ...
by Isabel_Eslabon_2G
Wed Dec 16, 2020 6:34 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Why isn't HF a strong acid?
Replies: 23
Views: 119

Re: Why isn't HF a strong acid?

F is very electronegative, so it does not want to dissociate with the H atom. This is why it is not a strong acid.

Among HCl, HBr, and HI, HI is the strongest acid because it gives up protons the easiest. The bond for HI is the longest, so it is the weakest.
by Isabel_Eslabon_2G
Wed Dec 09, 2020 7:16 pm
Forum: Hybridization
Topic: What is s-character?
Replies: 1
Views: 17

What is s-character?

Textbook problem 2F.15 asks "Noting that the bond angle of an sp3 hybridized atom is 109.58 and that of an sp2 hybridized atom is 1208, do you expect the bond angle between two hybrid orbitals to increase or decrease as the s-character of the hybrids is increased?" The answer is "As t...
by Isabel_Eslabon_2G
Tue Dec 08, 2020 4:21 pm
Forum: Industrial Examples
Topic: What are these?
Replies: 2
Views: 36

Re: What are these?

I don't remember many examples, but Lavelle did mention , which removes metals from solutions (from lecture on 11/25).
by Isabel_Eslabon_2G
Tue Dec 08, 2020 3:58 pm
Forum: Identifying Acidic & Basic Salts
Topic: Sapling #7
Replies: 3
Views: 26

Re: Sapling #7

Memorizing if salts are acidic/basic/neutral seems pretty difficult considering there could be other salts on the exam that you didn't prepare for. From my understanding, you need to determine what acid & base reacted to produce that salt. Looking at the strengths of both reactants will determin...
by Isabel_Eslabon_2G
Tue Dec 08, 2020 3:52 pm
Forum: Significant Figures
Topic: Things to remember for final?
Replies: 20
Views: 137

Re: Things to remember for final?

You only really need to know which acids/bases are strong and if you know the general rules for whether something is an acid or base, you can rule out if it's strong. There's too many weak acids/bases to memorize, but you can remember the strong ones easily.
by Isabel_Eslabon_2G
Tue Dec 08, 2020 3:49 pm
Forum: Calculating the pH of Salt Solutions
Topic: -OH vs OH-
Replies: 11
Views: 83

Re: -OH vs OH-

It's the same thing. In general, is how you'd normally write it when writing a chemical equation. is used more when writing diagrams or mechanisms to emphasize that the negative charge is from the oxygen, not the hydrogen.
by Isabel_Eslabon_2G
Wed Dec 02, 2020 9:55 pm
Forum: Lewis Acids & Bases
Topic: Lewis Acids & Bases
Replies: 12
Views: 86

Re: Lewis Acids & Bases

Lewis Acids are electron acceptors (I remember that because acids and acceptor both start with 'a'). These acids are electron deficient. I usually remember that if it has a positive charge, it can accept an electron (cations). Lewis Bases are electron donors. These bases may have negative charges (a...
by Isabel_Eslabon_2G
Wed Dec 02, 2020 9:42 pm
Forum: Lewis Acids & Bases
Topic: Ligands
Replies: 6
Views: 46

Re: Ligands

Ligands are ions/molecules that form coordinate covalent bonds by donating both electrons involved in the covalent bond. Because it donates electron pair(s), if you draw out the Lewis structure, it should have lone electron pairs. It is also generally a nonmetal in a coordination compound.
by Isabel_Eslabon_2G
Wed Dec 02, 2020 9:38 pm
Forum: Student Social/Study Group
Topic: Final Exam Study Tips
Replies: 47
Views: 217

Re: Final Exam Study Tips

My plan is to do the textbook problems listed in the outline. Since this final is cumulative, you also have to find time to review material from the previous 2 midterms. I suggest doing some of the harder textbook problems to review past content because I think it was mentioned some difficult questi...
by Isabel_Eslabon_2G
Wed Dec 02, 2020 9:33 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Sapling Week 9 HW Question 2
Replies: 11
Views: 94

Re: Sapling Week 9 HW Question 2

Hello. When determining coordination number, the coordination sphere consists of the elements in brackets. At first I thought the coordination number was 2, but that's because I was looking at Ba, which was outside the brackets. Fe is the central atom and has 4 Br atoms bound to it, which means the ...
by Isabel_Eslabon_2G
Sun Nov 29, 2020 5:32 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Textbook Problem 2E5
Replies: 3
Views: 28

Re: Textbook Problem 2E5

a) The shape of the ion is bent/angular.
b) The bond angle between the two O atoms are slightly less than 120 degrees due to the presence of a lone electron pair.
by Isabel_Eslabon_2G
Sat Nov 28, 2020 7:57 pm
Forum: Hybridization
Topic: Multiple Bonds with Hybridization
Replies: 6
Views: 27

Re: Multiple Bonds with Hybridization

I'm not sure if this is the right way to explain this, but when determining hybridization of an atom you look at the number of atoms it's attached to and the number of lone pairs that it has. The number of bonds between the atoms does not affect it. I am assuming Molecule #1 has a central atom with ...
by Isabel_Eslabon_2G
Sat Nov 28, 2020 7:11 pm
Forum: Octet Exceptions
Topic: Textbook Question 2.61
Replies: 3
Views: 33

Re: Textbook Question 2.61

I am not sure if this is correct, but I tried looking at alternate structures where the lone electron is not on the C. The structure where the lone electron is on C is the favored structure because that structure has all atoms with a formal charge of 0. If the lone electron is on an oxygen, the form...
by Isabel_Eslabon_2G
Sat Nov 28, 2020 7:02 pm
Forum: Student Social/Study Group
Topic: Midterm/Final Success?
Replies: 17
Views: 148

Re: Midterm/Final Success?

In my experience, I do all of the textbook problems in the outline and the UA problems on my own. When I have questions about certain topics, I utilize both this forum and chemistry videos on YouTube (I used these in high school and they really helped me). It's helpful to compile a list of condensed...
by Isabel_Eslabon_2G
Tue Nov 17, 2020 4:03 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: d vs s orbitals
Replies: 7
Views: 87

Re: d vs s orbitals

Hello. From how I understand it: 1. Electrons are added to the 4s orbitals before the 3d orbitals because the 4s orbitals are lower in energy when both are unoccupied. The 4s and 3d orbitals are very close in energy. After 4s orbitals are occupied, electrons must enter 3d state (then 3d is lower in ...
by Isabel_Eslabon_2G
Tue Nov 17, 2020 3:54 pm
Forum: Dipole Moments
Topic: dipoles and polarity
Replies: 2
Views: 18

Re: dipoles and polarity

I am pretty sure the answer is yes. A polar molecule is a molecule whose covalently shared electrons are shared unevenly. If a molecule has a permanent dipole moment, that would mean there is a permanent difference in charge in different regions of the molecule. Lavelle points out in the lecture on ...
by Isabel_Eslabon_2G
Tue Nov 17, 2020 3:49 pm
Forum: Bond Lengths & Energies
Topic: Higher Melting Point
Replies: 27
Views: 203

Re: Higher Melting Point

Comparing melting points involves looking at intermolecular attraction. To solve this you need to compare the London dispersion forces of CHI3 and CHF3. When comparing dispersion forces, CHI3's is stronger than CHF3's because the iodine in CHI3 has more electrons than the fluorine in CHF3. For dispe...
by Isabel_Eslabon_2G
Tue Nov 17, 2020 3:45 pm
Forum: Quantum Numbers and The H-Atom
Topic: Cr+ Ground State Electron Configuration
Replies: 2
Views: 29

Re: Cr+ Ground State Electron Configuration

I'm pretty sure that the 4s orbital has 1 electron because that is more stable that way. Lavelle explained it in the lecture on 10/26/2020.
by Isabel_Eslabon_2G
Tue Nov 17, 2020 3:41 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Textbook Problem 2A.3
Replies: 1
Views: 14

Re: Textbook Problem 2A.3

Hello.

I think that's actually problem 2A.4. 2A.3 asks for the configurations of

I think your answers for V4+ & Fe3+ are correct.
by Isabel_Eslabon_2G
Fri Nov 13, 2020 10:51 pm
Forum: Resonance Structures
Topic: Delocalized Electrons
Replies: 7
Views: 25

Re: Delocalized Electrons

From my understanding, delocalized electrons are electrons not associated with single atom or covalent bond. Resonance structures represent possible structures of a molecule because there are electrons not bound to a single atom/bond.
by Isabel_Eslabon_2G
Fri Nov 13, 2020 10:35 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: Textbook Problem 3f.5
Replies: 2
Views: 36

Re: Textbook Problem 3f.5

B) Butanol is more likely due to hydrogen bonding (this isn't present in diethyl ether). C) CHI3 is more likely. When comparing London dispersion forces, CHI3's is stronger than CHF3's because the iodine in CHI3 has more electrons than the fluorine in CHF3. Just to be clear, in CHF3 there is no hydr...
by Isabel_Eslabon_2G
Thu Nov 12, 2020 9:13 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Orbital levels
Replies: 1
Views: 13

Re: Orbital levels

Hello, From my understanding, the 4s orbital is lower in energy than the 3d orbital, but only slightly (in general, as energy levels increase; as they increase energies of orbitals become closer). After the 4s state is occupied, electrons must enter 3d state. Then 3d is lower in energy than 4s. When...
by Isabel_Eslabon_2G
Mon Nov 09, 2020 7:25 pm
Forum: Ionic & Covalent Bonds
Topic: # of Valence Electrons for Transition Metals [ENDORSED]
Replies: 1
Views: 271

# of Valence Electrons for Transition Metals [ENDORSED]

Hello.

This is a bit of a simple question but I am having some trouble understanding how to determine the number of valence electrons in transition metals?

I know that K has 1, C has 4, O has 6, etc. but what about ones like V and Ni?
by Isabel_Eslabon_2G
Mon Nov 09, 2020 7:21 pm
Forum: Ionic & Covalent Bonds
Topic: Textbook Question 2A.15 Part D
Replies: 1
Views: 18

Textbook Question 2A.15 Part D

Hello.

The question asks to write the most likely charge for the ions formed by Ga.

The answer is 3+. Why is this (my initial answer was 1+)?
My reasoning was because then there are full subshells now that there are no electrons in 4p?
by Isabel_Eslabon_2G
Thu Nov 05, 2020 5:05 pm
Forum: Student Social/Study Group
Topic: Studying Tips
Replies: 23
Views: 152

Re: Studying Tips

Hello! As many have already recommended, doing the textbook problems that Lavelle has in the Outlines on his website are super helpful. I would like to add that the last problems for each section are usually more important to understand because they are harder, so if you're short on time & feel ...
by Isabel_Eslabon_2G
Thu Nov 05, 2020 5:01 pm
Forum: Trends in The Periodic Table
Topic: Midterm 2 Study Group
Replies: 7
Views: 63

Re: Midterm 2 Study Group

I would like to be a part of this study group :). I think this would be very helpful. How would you like me & others to contact you?
by Isabel_Eslabon_2G
Thu Nov 05, 2020 9:21 am
Forum: Ionic & Covalent Bonds
Topic: Sapling Week 5/6 #16
Replies: 2
Views: 23

Sapling Week 5/6 #16

Hello, I am struggling with understanding this question: A cross-link is an ionic, covalent, or hydrogen bond that links one polymer chain to another and reduces the flexibility of the polymer chains. Several possible hydrogen bond cross links are shown between the two polymer chains in the image. I...
by Isabel_Eslabon_2G
Thu Nov 05, 2020 8:50 am
Forum: Ionic & Covalent Bonds
Topic: Lengths of Single & Double Bonds
Replies: 4
Views: 44

Lengths of Single & Double Bonds

I don't remember if Lavelle spoke on this already, so I will just ask about it here.
If we are asked about lengths of single & double bonds on exams, do we need to memorize common ones (like C=C, or C-H) or will they be given in the question? Or do we get a reference chart for it?
by Isabel_Eslabon_2G
Thu Nov 05, 2020 7:36 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8483
Views: 1467698

Re: Post All Chemistry Jokes Here

Not sure if this is chem-related but oh well.

Before heading out to the store, my sister told me "Hey, we're out of salt" to which I replied "0mg".
by Isabel_Eslabon_2G
Wed Oct 28, 2020 1:34 pm
Forum: Trends in The Periodic Table
Topic: Electron Affinity
Replies: 10
Views: 69

Re: Electron Affinity

Hello. A higher electron affinity means an atom is more readily accepting of electrons. In terms of energy, whenever atoms gain electrons, they release energy. From my understanding, this occurs whenever electrons are gained, whether they have high or low electron affinities, but because atoms with ...
by Isabel_Eslabon_2G
Wed Oct 28, 2020 1:30 pm
Forum: Properties of Light
Topic: UA Workshop Question
Replies: 4
Views: 58

UA Workshop Question

Hello, I am struggling with this problem: It is generally accepted that UVC lamps with 40 mJ/cm² at a wavelength of 250 nm can be used to disinfect surfaces and kill pathogens. If you leave a UVC lamp on to disinfect a 5 m² area, how many high energy photons are produced? The answer key says 2.52*10...
by Isabel_Eslabon_2G
Wed Oct 28, 2020 1:21 pm
Forum: Empirical & Molecular Formulas
Topic: Textbook Problem M.19
Replies: 8
Views: 82

Re: Textbook Problem M.19

Hello. I like to write the chemical equation out like this: (?) + O2 -> CO2 + H2O + N2 I just write caffeine as (?) because we don't know its molecular formula You need to use the masses of CO2, H20, & N2 to find the moles of C, H, & N (using stoichiometry). Use the masses of C, H, & N (...
by Isabel_Eslabon_2G
Wed Oct 28, 2020 9:43 am
Forum: Balancing Chemical Reactions
Topic: Problem for UA Workshop 1
Replies: 2
Views: 45

Problem for UA Workshop 1

Hello. I've had a bit of trouble balancing this one chemical equation: NaHCO_3 + C_6H_8O_7\rightarrow Na_3C_6H_5O_7+H_2O+CO_2 Can anyone help me? Also does anyone have tips about how to balance equations like this? I don't want to spend too much time on these questions on the midterm (I either take ...
by Isabel_Eslabon_2G
Wed Oct 28, 2020 9:34 am
Forum: Molarity, Solutions, Dilutions
Topic: UA Session Question
Replies: 2
Views: 40

Re: UA Session Question

Hello.

For part B you need to use the molarity from part A & use this formula:



M1=Molarity from Part A
V1= You are solving for this.
M2=5.60*10^-7
V2=0.235L

I did the conversion, but this formula needs to be in liters, so once you find the value of V1, convert back to mL.
by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:27 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Homework problem #8
Replies: 3
Views: 47

Re: Homework problem #8

The Lyman Series all contain the transition n=2 to n=1 and Balmer Series all contain the transition n=3 to n=2 From my understanding, these are the "common transitions" because they are the biggest energy gaps in the series (the energy levels converge as they increase). In all honesty, I d...
by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:21 pm
Forum: Einstein Equation
Topic: 1B.9 (7th edition)
Replies: 8
Views: 445

Re: 1B.9 (7th edition)

ohhh what okay then my textbook is messed up that makes so much more sense!!! Mine looks like this "1B.9 A lamp rated at emits violet light of wavelength 420 nm. How many photons of violet light can the lamp generate in 2.0 s? How many moles of photons are emitted in that time interval?" ...
by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:14 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Variables in Rydberg Equation
Replies: 5
Views: 64

Re: Variables in Rydberg Equation

Frequency is not the same thing as energy level.

When you are solving the problem, you solve for the frequency and use the frequency to find the energy level. This equation involves both frequency and energy level:

by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:11 pm
Forum: Einstein Equation
Topic: 1B.9 (7th edition)
Replies: 8
Views: 445

Re: 1B.9 (7th edition)

Where does the 32W come from in this problem?? I'm confused? The 32W is given in the problem: 1B.9 A lamp rated at 32W(1W=1J⋅s^−1) emits violet light of wavelength 420 nm. How many photons of violet light can the lamp generate in 2.0 s? How many moles of photons are emitted in that time interval? o...
by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:04 pm
Forum: Einstein Equation
Topic: 1B.9 (7th edition)
Replies: 8
Views: 445

Re: 1B.9 (7th edition)

Tikva Cohen 2I wrote:Where does the 32W come from in this problem?? I'm confused?


The 32W is given in the problem:

1B.9 A lamp rated at 32W(1W=1J⋅s^−1) emits violet light of wavelength 420 nm. How many photons of violet light can the lamp generate in 2.0 s? How many moles of photons are emitted in that time interval?
by Isabel_Eslabon_2G
Wed Oct 21, 2020 2:01 pm
Forum: Administrative Questions and Class Announcements
Topic: The Midterm Topics
Replies: 5
Views: 70

Re: The Midterm Topics

On Lavelle's CHEM14A website he posted an announcement saying: Midterm 1 covers material up to Wednesday of Week 3. This is up to Q19 in Sapling (quantum) homework. In Outline 2 below, all topics except the last 8 listed. MT 1 is to the end of 1D.2 in textbook. Quantum numbers, shape of orbitals, et...
by Isabel_Eslabon_2G
Wed Oct 21, 2020 1:57 pm
Forum: Properties of Light
Topic: Electromagnetic Sepectrum
Replies: 3
Views: 48

Re: Electromagnetic Sepectrum

From the practice/homework questions, I assume that we need to know wavelength boundaries for x-rays, infrared, microwaves, and others because those were asked in the homework. To memorize the general order, I use the mnemonic: Roman Men Invented Very Unusual X-Ray Guns Radio Waves, Microwaves, Infr...
by Isabel_Eslabon_2G
Wed Oct 14, 2020 10:04 pm
Forum: General Science Questions
Topic: Balancing equations
Replies: 17
Views: 151

Re: Balancing equations

Hello. I would just like to say that sometimes when I am deep into balancing an equation and I get something that works, what happens is I went too far and have something like: 4C_{2}H_{6} + 14O_2 \rightarrow 8CO_2 + 12H_2O when it really should be: 2C_{2}H_{6} + 7O_2 \rightarrow 4CO_2 + 6H_2O Altho...
by Isabel_Eslabon_2G
Wed Oct 14, 2020 9:50 pm
Forum: Properties of Electrons
Topic: Atomic Spectra and Exciting Electrons
Replies: 4
Views: 48

Re: Atomic Spectra and Exciting Electrons

I believe he mentioned this in one of the Audio-Visual Focus-Topic Videos (the Atomic Spectra video)on his website. When he was drawing out the different energy levels, he mentioned that if the frequency didn't correspond to an energy difference (n=1 to n=2 for example), then it wouldn't be absorbed...
by Isabel_Eslabon_2G
Wed Oct 14, 2020 9:41 pm
Forum: Student Social/Study Group
Topic: iPad vs Paper notes
Replies: 32
Views: 258

Re: iPad vs Paper notes

Hello. I have tried using an iPad in the past for notes and from my experience you can do a lot more versus taking regular notes. Some of my friends use iPads and Apple Pencils and they think it's really convenient because they can move things around on the screen and undo. It is convenient, but bec...
by Isabel_Eslabon_2G
Wed Oct 14, 2020 9:33 pm
Forum: Significant Figures
Topic: Easy 3 Rules
Replies: 9
Views: 112

Re: Easy 3 Rules

Hi! I've had trouble figuring out significant figure rules throughout my time in chemistry. Rule #3 (Anything after a decimal is counted as a significant number, any trailing zeros as well) For the number 0.00450, are there 3 or 5 significant figures? It's numbers like these that I'm always confused...
by Isabel_Eslabon_2G
Wed Oct 14, 2020 9:11 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Format
Replies: 12
Views: 118

Re: Midterm Format

Although I am not sure, I am assuming it is open ended because my TA talked about how we miss points if we have incorrect significant figures, wrong scientific notation, etc. But you should email your TA about it to be safe. Since this is somewhat high level chemistry, I would prepare for the worst ...
by Isabel_Eslabon_2G
Wed Oct 07, 2020 6:08 pm
Forum: Photoelectric Effect
Topic: Textbook Example 1B.2
Replies: 1
Views: 19

Re: Textbook Example 1B.2

I believe that NsubA is just the amount of photons in 1 mol of photons. So you're just multiplying Avogadro's constant by the energy of 1 photon in order to find the amount of energy in a mol of photons.

by Isabel_Eslabon_2G
Wed Oct 07, 2020 5:06 pm
Forum: Limiting Reactant Calculations
Topic: M.11 Fundamental Problem
Replies: 3
Views: 55

Re: M.11 Fundamental Problem

Hello. The limiting reactant of the first reaction is P4: Using 5.77 g P4, you produce 10.241 g P4O6. 5.77g P_{4} * \frac{1 mol P_{4}}{123.88gP_{4}}*\frac{1 mol P_{4}O_{6}}{1 molP_{4}}*\frac{219.88gP_{4}O_{6}}{1molP{4}O_{6}} Using 5.77 g O2, you produce 13.216 g P4O6, so the first reaction will resu...
by Isabel_Eslabon_2G
Mon Oct 05, 2020 11:19 am
Forum: Balancing Chemical Reactions
Topic: Help Balancing this Equation, Problem L.35
Replies: 6
Views: 74

Re: Help Balancing this Equation, Problem L.35

Hello. I think there might have been a typo in Equation #3. It’s actually Fe3Br8 + Na2CO3 = NaBr + CO2 + Fe3O4.
When I balanced it, I got Fe3Br8 + 4Na2CO3 = 8NaBr + 4CO2 + Fe3O4.
by Isabel_Eslabon_2G
Mon Oct 05, 2020 11:07 am
Forum: Balancing Chemical Reactions
Topic: Law of Conservation with Exothermic/Endothermic Reactions
Replies: 11
Views: 131

Re: Law of Conservation with Exothermic/Endothermic Reactions

I believe that heat does have more to do with the Conservation of Energy rather than mass. From my understanding, the energy that is shown in these reactions is just converting forms. For instance, an exothermic reaction results in bonds breaking. In this instance, potential energy is converted to k...
by Isabel_Eslabon_2G
Mon Oct 05, 2020 10:54 am
Forum: Properties of Light
Topic: Photoelectric Effect Module Quiz
Replies: 5
Views: 68

Photoelectric Effect Module Quiz

Hello. This is a question from the Photoelectric Effect Module. It has multiple parts: Light hits a sodium metal surface and the velocity of the ejected electron is 6.61*10^5 \frac{m}{s} . The work function for sodium is 150.6 \frac{kJ}{mol} . Part A asked for the kinetic energy of the ejected elect...

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