## Search found 103 matches

Sun Feb 23, 2020 10:25 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: cell diagrams Pt
Replies: 2
Views: 12

### Re: cell diagrams Pt

You need a solid to act as an electrode and Pt is an effective and common one bc it is resistant to oxidation, so if there is no solid we just assume it is Pt
Sun Feb 23, 2020 10:23 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Vant Hoff Equation
Replies: 6
Views: 15

### Vant Hoff Equation

What do we need to know about the Vant Hoff equation? Like will we need to ever calculate it? And what concepts about the equation should we know?
Sun Feb 23, 2020 10:17 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Platinum
Replies: 4
Views: 12

### Re: Platinum

I looked it up and i found "Platinum is used in electrochemical cells because it is resistant to oxidation- it will not easily react, which makes in excellent as an electrode as it will not take part in the Redox reactions occurring in electrochemical cells."
Sun Feb 23, 2020 10:13 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: | divider in cell diagram
Replies: 5
Views: 17

### Re: | divider in cell diagram

Yes, I believe they were both aqueous so you wouldn't separate them with a 'I'
Sun Feb 23, 2020 10:12 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt Bridge vs. Porous Disk
Replies: 2
Views: 10

### Re: Salt Bridge vs. Porous Disk

I think the only important difference for us to know is that when you write cell diagrams you put one 'I' between the anode and cathode for a disk and 'II' when there's a salt bridge between them
Sun Feb 23, 2020 10:10 pm
Forum: Van't Hoff Equation
Topic: Thermo in Test 2
Replies: 6
Views: 19

### Thermo in Test 2

What of thermodynamics do we need to know for test 2?
Sun Feb 23, 2020 10:07 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: STP
Replies: 13
Views: 28

### STP

Does anyone know what values we assume if told something happens under STP?
Sun Feb 23, 2020 9:58 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Calculation of Eo of a cell
Replies: 3
Views: 24

### Re: Calculation of Eo of a cell

I think what equation you'd use would depend on what info the question provides
Sun Feb 23, 2020 9:56 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Concentration and Cell Potential
Replies: 5
Views: 23

### Re: Concentration and Cell Potential

You relate these two with the Nernst equation: E=E*-RT/nF x lnQ. (the * is a knot, I just can't find one on my keyboard) So, if Q (concentration) increases then the term RT/nF x lnQ increases meaning you subtract a larger amount from E* and E is smaller. So I believe concentration and cell potential...
Sun Feb 23, 2020 9:52 pm
Forum: Balancing Redox Reactions
Topic: Test 2
Replies: 9
Views: 26

### Test 2

Does anyone know what day our test 2 get pushed back to?
Sun Feb 09, 2020 11:19 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Equations not on eq sheet
Replies: 1
Views: 15

### Equations not on eq sheet

Does anyone know what equations we will need to know on the midterm that won't be on the formula sheet?
Sun Feb 09, 2020 11:13 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Isothermal
Replies: 9
Views: 33

### Isothermal

Does isothermal mean the same thing as reversible?
Sun Feb 09, 2020 8:09 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Cs for monoatomic and diatomic
Replies: 4
Views: 22

### Re: Cs for monoatomic and diatomic

Monatomic compounds are composed of single atoms, and diatomic compounds are composed of molecules containing two atoms. what-are-the-seven-diatomic-elements-606623-v3-5b562dab46e0fb0037fee8c7.png Difference-Between-Monatomic-and-Diatomic-Comparison-Summary.png I don't know why the C s values are 3...
Sun Feb 09, 2020 8:02 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Entropy in reversible reactions
Replies: 2
Views: 15

### Entropy in reversible reactions

In the midterm review today Matthew said that S(sys)=-S(surr) when a process is reversible, but how do S(sys) and S(surr) relate when a process is irreversible?
Sun Feb 09, 2020 7:58 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Gibbs Free Energy on midterm
Replies: 5
Views: 19

### Gibbs Free Energy on midterm

Since we did not finish all the Gibbs free energy topics is the only equation we need to know for the midterm G=H-TS?
Sun Feb 09, 2020 7:51 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Cs for monoatomic and diatomic
Replies: 4
Views: 22

### Cs for monoatomic and diatomic

What does mono and diatomic mean and why are the Cs for them 3/2R and 5/2R?
Sat Feb 08, 2020 4:41 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Reversible vs Irriversible
Replies: 3
Views: 16

### Reversible vs Irriversible

Can anyone explain what makes an expansion reversible versus irreversible?
Tue Feb 04, 2020 12:29 am
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Heat vs Temp
Replies: 3
Views: 26

### Heat vs Temp

Can anybody explain the difference between heat and temperature?
Tue Feb 04, 2020 12:28 am
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Extensive Property
Replies: 4
Views: 16

### Extensive Property

What does it mean when someone says something is an extensive property? Like how is heat capacity an extensive property and specific heat capacity is not?
Tue Feb 04, 2020 12:18 am
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Lyndon's Step Up 2/3
Replies: 1
Views: 38

### Lyndon's Step Up 2/3

I had to leave early from Lyndon's step-up today, does anyone have the answers to the worksheet?
Tue Feb 04, 2020 12:16 am
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Reversible Reactions
Replies: 1
Views: 6

### Reversible Reactions

Can anybody explain what it means for a reaction to be reversible/irreversible?
Sun Jan 26, 2020 8:09 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: enthalpy changes
Replies: 2
Views: 8

### Re: enthalpy changes

I doubt we will, that would suck, but maybe ask your TA for confirmation
Sun Jan 26, 2020 8:05 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Reversible Reactions
Replies: 3
Views: 14

### Re: Reversible Reactions

I think technically all reactions can be reversible when put under certain conditions, but if you mean when we double-arrow a reaction I believe it is because it doesn't fully dissociate or the reverse reaction is likely to occur
Sun Jan 26, 2020 8:00 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: exo thermic
Replies: 11
Views: 25

### Re: exo thermic

In an exothermic reactant you can treat heat like a product so if you "added product" (increased heat) the equilibrium would shift left towards the reactants
Sun Jan 26, 2020 7:59 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: percent ionization
Replies: 5
Views: 12

### Re: percent ionization

Because you are subtracting a very minuscule amount from a much larger initial amount so the subtraction becomes negligible. Like if I have \$10,000 and I give away \$1 I would basically still have \$10,000.
Wed Jan 22, 2020 8:25 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6B.9 (a)
Replies: 3
Views: 18

### Re: 6B.9 (a)

The [H3O+] is 1.5M
Wed Jan 22, 2020 8:24 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6B.9 (a)
Replies: 3
Views: 18

### 6B.9 (a)

For this problem I keep taking the -log of [H3O+] to find the pH and getting -0.176 but the answer book says it's +0.176, what am I doing wrong?
Thu Jan 16, 2020 1:30 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Inert Gas and Le Chatliers
Replies: 7
Views: 25

### Inert Gas and Le Chatliers

Why does adding an inert gas not effect an equation?
Thu Jan 16, 2020 1:28 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K units
Replies: 10
Views: 35

### Re: K units

I think it's because K is an activity and activities don't have units.
Wed Jan 15, 2020 9:52 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6D.3
Replies: 1
Views: 14

### 6D.3

Can anybody explain how to do 6D.3?
Wed Jan 15, 2020 9:35 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6B.9
Replies: 1
Views: 10

### 6B.9

Can anyone help me with the first two rows of 6B.9?
Wed Jan 15, 2020 9:28 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Negative pH
Replies: 2
Views: 13

### Negative pH

What does it mean if a pH is negative?
Wed Jan 15, 2020 9:07 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: When to use Kc or Kp
Replies: 2
Views: 8

### When to use Kc or Kp

When am i supposed to use Kc rather than Kp and vice versa? Because i heard that you use Kp for gasses but in an example problem during one of the step-ups we used Kc for an equation with just gasses.
Wed Jan 15, 2020 9:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Inert Gas
Replies: 5
Views: 23

### Inert Gas

What is an inert gas?
Wed Jan 15, 2020 9:00 pm
Forum: Ideal Gases
Topic: ICE tables
Replies: 9
Views: 49

### Re: ICE tables

I think it would depend on the information given in the question (concentration or pressure). The units for pressure are usually atm or bar.
Wed Jan 15, 2020 8:58 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Kb and Ka
Replies: 2
Views: 14

### Re: Kb and Ka

Ka x Kb = 10^-14 so if you have Kb and are asked to find Ka then you do 10^-14/Kb.
I am not sure how to find the pH though.
Wed Jan 15, 2020 8:57 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE tables
Replies: 4
Views: 10

### Re: ICE tables

I think you use ICE tables when you're given K and an initial concentration and are asked to find a final concentration.
Sat Dec 07, 2019 3:58 pm
Forum: Lewis Acids & Bases
Topic: 6.21
Replies: 2
Views: 17

### 6.21

On question 6.21 in the textbook why can't the Oxygen on the Thymine accept protons?
Sat Dec 07, 2019 3:48 pm
Forum: Lewis Acids & Bases
Topic: 6.5
Replies: 1
Views: 23

### 6.5

Can anyone explain 6.5 part c from the textbook?
Sat Dec 07, 2019 10:56 am
Forum: Hybridization
Topic: N-triple bond-N pi bond hybridization
Replies: 4
Views: 43

### Re: N-triple bond-N pi bond hybridization

(N2p, N2p) because pi bonds happen when p orbitals overlap. does this mean that pi bonds can only be formed in p orbitals only? Yeah i'm pretty sure by definition pi bonds form between the overlapping of p orbitals. There could be exceptions I don't know of but when you look it up it says overlappi...
Sat Dec 07, 2019 10:54 am
Forum: Lewis Structures
Topic: Priority of factors when drawing Lewis structures
Replies: 4
Views: 45

### Re: Priority of factors when drawing Lewis structures

I'm not sure but I know that having an octet is the most important thing when drawing lewis structures and then usually from making sure each atom has an octet you can figure out how to best balance the formal charges. What if there is more than one way to make all atoms have eight electrons? Then ...
Sat Dec 07, 2019 12:53 am
Forum: Hybridization
Topic: N-triple bond-N pi bond hybridization
Replies: 4
Views: 43

### Re: N-triple bond-N pi bond hybridization

(N2p, N2p) because pi bonds happen when p orbitals overlap.
Sat Dec 07, 2019 12:50 am
Forum: Naming
Topic: Naming Anionic Ligands
Replies: 3
Views: 33

### Re: Naming Anionic Ligands

Either will work, but on Dr. Levelle's pdf the ones in the starred column are what he will usually use i believe.
Sat Dec 07, 2019 12:47 am
Forum: Sigma & Pi Bonds
Topic: Characteristics
Replies: 2
Views: 45

### Re: Characteristics

I think you could relate it to chelating ligands because a ligand cant create a ring around a metal if it cant rotate meaning it would have to have the right type of bond (single vs double) in the right places.
Sat Dec 07, 2019 12:43 am
Forum: Naming
Topic: oxidation number
Replies: 3
Views: 31

### Re: oxidation number

I'm pretty sure it can get up tp 6.
Sat Dec 07, 2019 12:37 am
Forum: Naming
Topic: Parentheses in naming
Replies: 1
Views: 22

### Re: Parentheses in naming

I thought that polydentate ligands were put in parentheses when there is multiple of them and that explains 9C.4 but not 9C.3 so i'm confused too
Sat Dec 07, 2019 12:34 am
Forum: Hybridization
Topic: 2s for Carbon hybridization
Replies: 3
Views: 23

### Re: 2s for Carbon hybridization

On a test though when writing out hybridization i think it doesn't matter if you write the 2 in front as long as the sp^2 part is correct.
Sat Dec 07, 2019 12:33 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelation
Replies: 4
Views: 41

### Re: Chelation

Chelation is when a polydentate ligand forms a ring around its central atom. All polydentate ligands are said to be chelating.
Sat Dec 07, 2019 12:30 am
Forum: Lewis Structures
Topic: Priority of factors when drawing Lewis structures
Replies: 4
Views: 45

### Re: Priority of factors when drawing Lewis structures

I'm not sure but I know that having an octet is the most important thing when drawing lewis structures and then usually from making sure each atom has an octet you can figure out how to best balance the formal charges.
Sat Dec 07, 2019 12:23 am
Forum: Naming
Topic: writing formula of a given name
Replies: 5
Views: 63

### Re: writing formula of a given name

At the review session we were told that when going from name to formula the order of the ligands does not matter.
Sat Dec 07, 2019 12:21 am
Forum: Administrative Questions and Class Announcements
Topic: Final Exam Place
Replies: 3
Views: 58

### Re: Final Exam Place

14A-1, 10am class: Last name A-L in CS 50.
Last name M-Z in Lakretz 110.
14A-3, 12noon class: Last name A-G in CS 24.
Last name H-M in CS 76.
Last name N-Z in Franz 1178.
14A-4, 2pm class: Last name A-Z in Moore 100.
Sat Dec 07, 2019 12:14 am
Forum: Lewis Acids & Bases
Topic: Stronger Base and Stronger Acid
Replies: 3
Views: 22

### Re: Stronger Base and Stronger Acid

For acids you look at either:
1. Bond length
2. Resulting anion stability.
i'm not sure about bases though
Sat Dec 07, 2019 12:13 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelate vs Polydentate
Replies: 6
Views: 55

### Re: Chelate vs Polydentate

Chelates form a ring around the central atom, whereas polydentate ligands allow more than one of its binding sites to be occupied. I think that a polydentate ligand can be a chelate, but they are not necessarily a chelate. In the review session i'm pretty sure Matthew said all polydentate ligands c...
Sat Dec 07, 2019 12:12 am
Forum: Polyprotic Acids & Bases
Topic: Definition of Polyprotic
Replies: 5
Views: 45

### Re: Definition of Polyprotic

Polyprotic acids can donate more than one proton and polyprotic bases can accept more than one proton. For example, H2SO4 is a polyprotic acid and its conjugate base SO4^2- would be a polyprotic base.
Sat Dec 07, 2019 12:06 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: EDTA
Replies: 3
Views: 30

### Re: EDTA

It's hexadentate and it is also a chelating ligand.
Sat Dec 07, 2019 12:06 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelate vs Polydentate
Replies: 6
Views: 55

### Re: Chelate vs Polydentate

Chelates form a ring around the central atom, whereas polydentate ligands allow more than one of its binding sites to be occupied. I think that a polydentate ligand can be a chelate, but they are not necessarily a chelate. In the review session i'm pretty sure Matthew said all polydentate ligands c...
Sat Dec 07, 2019 12:04 am
Forum: Identifying Acidic & Basic Salts
Topic: Basic Salts
Replies: 2
Views: 29

### Re: Basic Salts

If one of the ions in a salt comes from a weak acid or base then the salt will change the pH.
Wed Nov 27, 2019 1:25 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Acid/base strength?
Replies: 4
Views: 32

### Re: Acid/base strength?

A strong acid or base will completely dissociate in water, leading to a higher concentration of [H+] or [OH-] in the solution which contributes to a more extreme pH or pOH.
Wed Nov 27, 2019 1:22 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Acids
Replies: 13
Views: 89

### Re: Acids

Probably the 7 main strong & weak acids he went over in class, and we will probably have to know bases too, but i'm sure Dr. Lavelle will tell us as we get closer to the final.
Wed Nov 27, 2019 1:21 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: How to take the log to get the pH?
Replies: 8
Views: 50

### Re: How to take the log to get the pH?

If you were given a Hydrogen concentration of [H+]=0.1M, for example, and asked to find the pH, you would plug the concentration into the formula pH=-log[H+]; pH=-log[0.1M], and just plug it into your calculator.
Wed Nov 27, 2019 1:16 pm
Forum: Lewis Acids & Bases
Topic: Lewis acid vs regular acid?
Replies: 4
Views: 22

### Re: Lewis acid vs regular acid?

They are the same thing but the definition of an Acid can be defined as both a Lewis Acid (accepts e- pair) or Bronstead Acid (proton donor).
Wed Nov 27, 2019 1:13 pm
Forum: Dipole Moments
Topic: Hydrogen Bonding Sites
Replies: 9
Views: 57

### Re: Hydrogen Bonding Sites

Any site where a Hydrogen atom bonds to a Nitrogen, Oxygen, or Fluorine atom.
Mon Nov 25, 2019 4:15 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination compound
Replies: 5
Views: 43

### Re: Coordination compound

I believe they are all just synonyms of each other
Mon Nov 25, 2019 4:13 pm
Forum: Lewis Acids & Bases
Topic: Proton acceptor and proton donor?
Replies: 33
Views: 140

### Re: Proton acceptor and proton donor?

The proton acceptor is the Bronstead Base/ e- pair donator (Lewis Base), and the proton donor is the Bronstead Acid/ e- pair acceptor (Lewis Acid).
Mon Nov 25, 2019 4:10 pm
Forum: Air Pollution & Acid Rain
Topic: Clean Coal vs Dirty Coal?
Replies: 16
Views: 123

### Re: Clean Coal vs Dirty Coal?

Clean coal contains more carbon and less sulfur meaning it is better or "cleaner" for the environment whereas dirty coal is the opposite.
Mon Nov 25, 2019 4:09 pm
Forum: Bronsted Acids & Bases
Topic: Weak vs Strong Acid/Bases
Replies: 3
Views: 28

### Re: Weak vs Strong Acid/Bases

I think it would be a weak acid/base still because the definition of a strong acid/base is it completely ionizes in water, so I would assume that if an acid or base did not completely ionize in water, even if it did for a notable percentage, it would still be a weak one just because it does not fit ...
Mon Nov 25, 2019 4:05 pm
Forum: Student Social/Study Group
Topic: A joke to brighten your day
Replies: 3
Views: 81

### Re: A joke to brighten your day

Heres a joke for you too:
Ya'll wanna hear a joke about chemistry or Na?
Mon Nov 25, 2019 1:07 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs linear
Replies: 56
Views: 302

### Re: Bent vs linear

Linear has no lone electrons so it would be AX but a bent shape has a lone pair so it would be AXE.
Sat Nov 16, 2019 12:53 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: T Shape
Replies: 7
Views: 41

### Re: T Shape

If he never went over it in the lecture i'd read it in the textbook just in case.
Sat Nov 16, 2019 12:51 pm
Forum: General Science Questions
Topic: Test 2
Replies: 7
Views: 43

### Re: Test 2

Since Test 2 will only be on topics covered in the last 3 lectures i'd assume it's going to be mainly concept based.
Sat Nov 16, 2019 12:49 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: Test 2
Replies: 5
Views: 32

### Re: Test 2

According to an email from my TA test 2 will include: -Use the Valence-Shell Electron-Pair Repulsion Model (VSEPR) to determine the shape of inorganic, organic, and small biological molecules, cations, and anions. -Use bond dipole moments and shape to determine if a molecule is polar or non-polar. -...
Fri Nov 15, 2019 5:59 pm
Forum: Sigma & Pi Bonds
Topic: Sigma & Pi Bonds
Replies: 4
Views: 42

### Re: Sigma & Pi Bonds

We are going over Sigma & Pi bonds on Monday 11/18.
Thu Nov 07, 2019 7:10 pm
Forum: Photoelectric Effect
Topic: Midterm 1
Replies: 9
Views: 111

### Re: Midterm 1

Emily_4B wrote:Do you guys know if we’ll get the midterm back or be able to look at it in office hours to review this question?

My TA went over the midterm during discussion so maybe yours will too.
Thu Nov 07, 2019 7:08 pm
Forum: Ionic & Covalent Bonds
Topic: Bond Strength
Replies: 12
Views: 72

### Re: Bond Strength

Ionic because the electronegativity difference between the two atoms in an ionic bond are usually greater than the electronegativity difference between atoms in covalent bonds.
Thu Nov 07, 2019 7:04 pm
Forum: Ionic & Covalent Bonds
Topic: Why is the ionization energy of nitrogen higher than that of oxygen's?
Replies: 11
Views: 67

### Re: Why is the ionization energy of nitrogen higher than that of oxygen's?

Nitrogen has symmetry in it's 2p orbital (1 e- in each sub shell) and no electron-electron repulsion whereas Oxygen has one more electron than Nitrogen meaning its 2px orbital has electron-electron repulsion so its easier to ionize the fourth electron in the 2p orbital.
Thu Nov 07, 2019 6:44 pm
Forum: Lewis Structures
Topic: Expanded Octet
Replies: 10
Views: 61

### Re: Expanded Octet

If they have a d orbital they can expand their octet
Thu Nov 07, 2019 6:42 pm
Forum: General Science Questions
Topic: Week 6 homework problems
Replies: 7
Views: 66

### Re: Week 6 homework problems

I think this week we covered topic 2D
Sat Nov 02, 2019 6:05 pm
Forum: Trends in The Periodic Table
Replies: 2
Views: 22

According to the textbook, the atomic radius is half the distance between the centers of neighboring atoms and the ionic radius is the contribution of an ion to the distance between neighboring ions in a solid ionic compound. You can find out which isoelectronic ion has a larger radius by taking nuc...
Sat Nov 02, 2019 5:53 pm
Forum: Octet Exceptions
Topic: Cl as an expanded octet
Replies: 3
Views: 29

### Re: Cl as an expanded octet

Since Cl is in the third period it can hold electrons in its d shell (3d) and form an expanded octet. I googled it and found the example: ClF3
Sat Nov 02, 2019 5:48 pm
Forum: Lewis Structures
Topic: Expanded Valence Shells
Replies: 3
Views: 23

### Re: Expanded Valence Shells

When atoms have d shells they can hold more than 8 electrons
Sat Nov 02, 2019 5:47 pm
Forum: Trends in The Periodic Table
Topic: Period Trends
Replies: 4
Views: 22

### Re: Period Trends

Sat Nov 02, 2019 5:45 pm
Forum: Electronegativity
Topic: What is isoelectronic?
Replies: 13
Views: 56

### Re: What is isoelectronic?

Atoms are isoelectronic when they have the same number of electrons. For example, N2-, O-, and F are isoelectronic.
Thu Oct 24, 2019 6:17 pm
Forum: Lewis Structures
Topic: Ion lewis structure
Replies: 9
Views: 59

### Re: Ion lewis structure

I don't think it matters, as long as you follow the octet rule and put the bracket and the ion's respective charge around the lewis structure.
Thu Oct 24, 2019 6:14 pm
Forum: Properties of Electrons
Topic: Electron density
Replies: 2
Views: 48

### Re: Electron density

What do you mean? I think they do have electron density, which is represented by their respective orbitals.
Thu Oct 24, 2019 6:09 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration p orbital
Replies: 2
Views: 26

### Re: Electron Configuration p orbital

I don't think we have to know it for the test, but it helps to understand more about an atom's electron configuration.
Thu Oct 24, 2019 6:05 pm
Forum: Properties of Light
Topic: photoelectric effect
Replies: 4
Views: 41

### Re: photoelectric effect

When you increase intensity of light, you are increasing the number of photons emitted by the light, not to be confused with the energy per photon emitted by the light. To increase the energy per photon of the light and therefore eject more electrons from the metal, you'd increase the frequency (dec...
Thu Oct 24, 2019 5:52 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Noble Gas Configuration
Replies: 10
Views: 74

### Re: Noble Gas Configuration

I'm pretty sure you can use either type of configuration you want, unless the question asks for one or the other.
Thu Oct 17, 2019 6:30 pm
Forum: Properties of Light
Topic: Problem 1A9. How to determine which values the reading event corresponds to?
Replies: 4
Views: 40

### Re: Problem 1A9. How to determine which values the reading event corresponds to?

Match the values to table 1A.1 on page 6.
Thu Oct 17, 2019 6:25 pm
Forum: Quantum Numbers and The H-Atom
Topic: Subshells based on n
Replies: 3
Views: 39

### Re: Subshells based on n

oh you right lol my bad, so it'd be these i think
n=4, l=0, m=0
" , l=1, m=-1, 0, or +1
" , l=2, m=-2, -1, 0, +1, +2
" , l=3, m=-3, -2, -1, 0, +1, +2, +3
so 16
Thu Oct 17, 2019 6:12 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: magnetic quantum number, ml
Replies: 2
Views: 15

### Re: magnetic quantum number, ml

The orientation of the orbitals is basically how they lie on the x-y-z plane.
Thu Oct 17, 2019 6:07 pm
Forum: Photoelectric Effect
Topic: Different metals
Replies: 2
Views: 27

### Re: Different metals

Yes, the effect systematically works the same, varying with the type of metal used in the experiment because if you change the metal the energy per photon needed to omit an electron (threshold energy) may change.
Thu Oct 17, 2019 5:59 pm
Forum: Quantum Numbers and The H-Atom
Topic: Subshells based on n
Replies: 3
Views: 39

### Re: Subshells based on n

4; l= 0, 1, 2, or 3
Thu Oct 17, 2019 5:56 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: G orbital
Replies: 6
Views: 42

### Re: G orbital

I don't think the G orbital is portrayed in the periodic table at all, I'm pretty sure the periodic table only goes up to f, and I believe Dr. Lavelle told us we don't need to know about the G orbital anyways as well, probably just that it exists.
Mon Oct 07, 2019 5:44 pm
Forum: Properties of Light
Topic: Photons
Replies: 7
Views: 58

### Photons

Increasing intensity means you increase the number of photons right? And if one photon interacts with one electron, then why doesn't increasing intensity lead to increased electrons emitted? And why doesn't more photons equal more energy?
Mon Oct 07, 2019 5:36 pm
Forum: Significant Figures
Topic: Homework
Replies: 4
Views: 60

### Re: Homework

We do homework problems from the book on recently learned topics, but this week even though we are learning Quanta he said we can still do Review problems to help study for the test this week.
Mon Oct 07, 2019 5:34 pm
Forum: Molarity, Solutions, Dilutions
Topic: Dilutions
Replies: 3
Views: 50

### Re: Dilutions

Yeah, molarity is always mol/L so you have to convert given units into mol and L to get the correct number for molarity.
Mon Oct 07, 2019 5:32 pm
Forum: Empirical & Molecular Formulas
Topic: Fundamental F.19
Replies: 3
Views: 39

### Re: Fundamental F.19

Isn't the molar mass given in the problem as 194.19 g/mol?
Mon Oct 07, 2019 5:27 pm
Forum: SI Units, Unit Conversions
Topic: Writing formulas
Replies: 4
Views: 71

### Re: Writing formulas

I think we do have to know how to do this. I know for my AP chem class in high school we were just told to memorize certain common molecules and their charges like nitrate, phosphate, etc., so unless it's given in the question on the test I assume we just have to memorize them.
Wed Oct 02, 2019 3:59 pm
Forum: Balancing Chemical Reactions
Topic: Equations Balancing
Replies: 6
Views: 120

### Re: Equations Balancing

When I balance equations I write out the equation and draw a vertical line down from the arrow and on each side list how many of each atom/molecule is there. Then I just go one atom/molecule down the list at a time, crossing out initial atom/molecule counts with the new ones when I add a coefficient...
Wed Oct 02, 2019 3:44 pm
Forum: Properties of Light
Topic: Angstrom Unit [ENDORSED]
Replies: 2
Views: 48

### Re: Angstrom Unit[ENDORSED]

It's the unit we use when measuring bond lengths. It's equivalent to 10^-10 meters, like how one nanometer equals 10^-9 meters, an Angstrom equals 10^-10 meters, and then we apply the term to bond lengths.