Search found 94 matches

by Griffin G
Sun Mar 07, 2021 11:47 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: E vs E naught
Replies: 36
Views: 67

Re: E vs E naught

E naught is E in standard conditions.
by Griffin G
Sun Mar 07, 2021 11:46 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: lnQ
Replies: 12
Views: 158

Re: lnQ

Yes, you do need to use the coefficients as exponents.
by Griffin G
Sun Mar 07, 2021 11:46 pm
Forum: Balancing Redox Reactions
Topic: Half-Reactions
Replies: 11
Views: 35

Re: Half-Reactions

Half-reactions are most likely going to be things we will be asked to produce.
by Griffin G
Sun Mar 07, 2021 11:45 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Notation
Replies: 5
Views: 33

Re: Cell Notation

I like to think the order in the cell notation is directly relative to the order in the actual half-cell. The electrode is furthest away from the salt bridge, the solution is closer, and the ions that can travel through the bridge are the closest.
by Griffin G
Sun Mar 07, 2021 6:38 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Determining Anode vs Cathode
Replies: 22
Views: 38

Determining Anode vs Cathode

When we are given that a galvanic cell consists of two chambers with solution x and y respectively, how do we determine which is the anode and which is the cathode?
by Griffin G
Sun Feb 28, 2021 10:45 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Moles of Electrons
Replies: 9
Views: 52

Re: Moles of Electrons

They're the same thing! The #of electrons divided by avogadro's number = moles of electrons.
by Griffin G
Sun Feb 28, 2021 10:44 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Gibbs free energy
Replies: 18
Views: 264

Re: Gibbs free energy

Standard Gibb's free energy is the gibbs free energy at standard conditions for temperature, pressure, etc.
by Griffin G
Sun Feb 28, 2021 10:43 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt Bridge
Replies: 19
Views: 34

Re: Salt Bridge

A salt bridge essentially lets the the negative ions on the cathode side to travel over to the anode side, so that the electrons will continue to flow towards the cathode.
by Griffin G
Sun Feb 28, 2021 10:42 pm
Forum: Balancing Redox Reactions
Topic: Standard Potentials and Reactions
Replies: 12
Views: 23

Re: Standard Potentials and Reactions

Each question will probably provide the relevant/necessary values. Looking at how this course is laid out, there's no way we would be expected to memorize any of those values, and definitely not all of them.
by Griffin G
Sun Feb 28, 2021 10:41 pm
Forum: Balancing Redox Reactions
Topic: Balancing Acidic Versus Basic Solutions
Replies: 20
Views: 39

Re: Balancing Acidic Versus Basic Solutions

Think about which solution already has an abundance of H^+ and which has an abundance of OH^-.
by Griffin G
Sun Feb 21, 2021 9:33 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Relation to Internal Energy
Replies: 4
Views: 22

Re: Relation to Internal Energy

Basically like,,i a situation isn't doing any work, the internal energy is the same as the enthalpy, because enthalpy is the heat energy stored in a system.
by Griffin G
Sun Feb 21, 2021 9:32 pm
Forum: Phase Changes & Related Calculations
Topic: Vapor vs gas
Replies: 101
Views: 273

Re: Vapor vs gas

Same thing. If a chemical is usually in a liquid state, one might refer to the gaseous form as a vapor but the definition of both is identical.
by Griffin G
Sun Feb 21, 2021 9:31 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Bomb calorimeter
Replies: 9
Views: 26

Re: Bomb calorimeter

Bomb calorimeter = constant volume.
by Griffin G
Sun Feb 21, 2021 9:28 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Hfus
Replies: 9
Views: 22

Re: Hfus

Hfusion is for the phase change between solid and liquid.
by Griffin G
Sun Feb 21, 2021 9:27 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Different Gas Constants
Replies: 9
Views: 39

Re: Different Gas Constants

Honestly you can always use units to figure it out. Whichever constant has the desired units is the one to pick.
by Griffin G
Sun Feb 21, 2021 9:24 pm
Forum: Phase Changes & Related Calculations
Topic: Steam
Replies: 32
Views: 141

Re: Steam

Steam will do more damage because there is more energy in the steam than in liquid water of the same temperature.
by Griffin G
Sun Feb 21, 2021 9:21 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Calorimeter Calibration
Replies: 4
Views: 19

Calorimeter Calibration

Sorry to ask, but I'm still confused as to how to calibrate a calorimeter and how to use that value.
by Griffin G
Sun Feb 21, 2021 9:19 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Finding T
Replies: 12
Views: 47

Re: Finding T

If T is represented just as T, not as delta T, then that means T is a constant for a specific situation and the question should give it.
by Griffin G
Sun Feb 21, 2021 9:17 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Meaning of K
Replies: 52
Views: 107

Re: Meaning of K

Yes K is always the equilibrium constant we learned about in 14a.
by Griffin G
Sun Feb 21, 2021 9:16 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Delta G and G naught
Replies: 38
Views: 113

Re: Delta G and G naught

Anything "naught" is typically at standard conditions. Most things don't occur under standard conditions, so you would have to use deltaG instead. Think of deltaGnaught as like, the unobtainable ideal.
by Griffin G
Sun Feb 21, 2021 9:14 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Spontaneity of a System
Replies: 37
Views: 88

Re: Spontaneity of a System

Basically, use the equeation deltaG=deltaH - TdeltaS. The delta G value will tell you if the rxn is spontaneous or not.
by Griffin G
Sun Feb 21, 2021 9:13 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: entropy positive value
Replies: 30
Views: 61

Re: entropy positive value

Entropy will always have a net increase, no matter what happens. The disorder of the universe is constantly increasing.
by Griffin G
Sun Feb 21, 2021 9:12 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Isolated System
Replies: 8
Views: 22

Isolated System

Is it ever possible to create a system that is truly, 100% isolated? I feel like it's impossible to fully shield a region from the outside universe without at least a microscopic amount of energy entering and exiting.
by Griffin G
Sun Feb 21, 2021 9:11 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Which R value to choose
Replies: 11
Views: 30

Re: Which R value to choose

Honestly whenever you aren't sure which constant to use, always refer to the units and find the one that will give you the proper units in the end.
by Griffin G
Sun Feb 07, 2021 11:01 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: enthalpy and heat
Replies: 10
Views: 58

Re: enthalpy and heat

Q is heat, and it is usually just a single number, where H is enthalpy and it's usually thought of as change of H.
by Griffin G
Sun Feb 07, 2021 11:00 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Atoms, Linear, Non- Linear Molecules?
Replies: 9
Views: 27

Re: Atoms, Linear, Non- Linear Molecules?

CO2 is linear, because it's nonpolar.
by Griffin G
Sun Feb 07, 2021 10:58 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Can heat capacities be negative?
Replies: 52
Views: 163

Re: Can heat capacities be negative?

No they can't be. All matter has the ability to take in heat.
by Griffin G
Sun Feb 07, 2021 10:56 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Calorimeter Heat Capacity
Replies: 4
Views: 16

Calorimeter Heat Capacity

What's the best way to remember how to calculate the specific heat capacity of a calorimeter?
by Griffin G
Sun Feb 07, 2021 10:55 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Specific heat value
Replies: 11
Views: 21

Re: Specific heat value

If the same specific heat value appears on both sides of an equation you can just divide them out.
by Griffin G
Sun Feb 07, 2021 10:52 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Negative Sign
Replies: 16
Views: 46

Re: Negative Sign

I believe it goes on the side that is losing heat, aka exothermic. Like, the water is negative if an ice cube is dropped into it.
by Griffin G
Sun Jan 24, 2021 11:09 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Sapling Week 2 #7
Replies: 8
Views: 54

Re: Sapling Week 2 #7

Na+ doesn't affect the pH.
by Griffin G
Sun Jan 24, 2021 11:08 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Neutral Solution
Replies: 9
Views: 76

Re: Neutral Solution

10^-7, and that is important because it means OH- is also 10^-7.
by Griffin G
Sun Jan 24, 2021 11:07 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: When to use ICE box
Replies: 23
Views: 118

Re: When to use ICE box

Use the ICE box whenever you're trying to figure out how concentrations change before and after a reaction reaches equilibrium, basically.
by Griffin G
Sun Jan 24, 2021 11:06 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Sapling Number 5
Replies: 18
Views: 95

Re: Sapling Number 5

This one is tricky because you have a lot of moving parts. But basically, if you can lockdown the BH+ value, you just add that to B.
by Griffin G
Sun Jan 24, 2021 11:04 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Percent Ionization
Replies: 7
Views: 46

Re: Percent Ionization

The percent ionization is like, the percent of acid turned into the conjugate base when the reaction reaches equilibrium. So, basically, you take the concentration of whatever the conjugate base is, divide that by the INITIAL (before the reaction started [ in this case that is 0.1029M]) concentratio...
by Griffin G
Sun Jan 17, 2021 8:35 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kw constant
Replies: 25
Views: 64

Re: Kw constant

A solvent like H2O is usually in such a large excess that it's affect on the system is so minimal it's a waste of time to include it.
by Griffin G
Sun Jan 17, 2021 8:33 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE table equilibrium
Replies: 8
Views: 37

Re: ICE table equilibrium

If the reaction is going towards products, there will be positive X's on the product side and negative on the reagent side. The opposite is also true.
by Griffin G
Sun Jan 17, 2021 8:32 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Sapling question 9
Replies: 5
Views: 63

Re: Sapling question 9

Use the positive value from the quadratic equation, not the negative one.
by Griffin G
Sun Jan 17, 2021 8:32 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Temperature
Replies: 12
Views: 101

Re: Temperature

Yes. The temperature can change, but that will result in a different K value. However, if the temp were to suddenly change, and all conc.s remained constant, q wouldn't change.
by Griffin G
Sun Jan 17, 2021 8:21 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Quotient
Replies: 12
Views: 452

Re: Quotient

Q is calculated the same way as K, just when the system is not at equilibrium.
by Griffin G
Mon Jan 11, 2021 3:23 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Clarification of terminology
Replies: 15
Views: 129

Re: Clarification of terminology

All of that is correct. A lot of those phrases are simply different ways to personify reactions, which makes it easier to comprehend. When K is larger than 1000, there is simply more product than reagent. One could describe this in a plethora of ways, by saying the reaction is product heavy, it sits...
by Griffin G
Mon Jan 11, 2021 3:21 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: change in K
Replies: 22
Views: 109

Re: change in K

Temperature does change K. The only two variables that can change K are temperature, and the exact reaction that is occurring. Change the reaction or change the temperature, you change K.
by Griffin G
Mon Jan 11, 2021 3:20 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Effect of Catalyst
Replies: 7
Views: 42

Re: Effect of Catalyst

Catalysts don't change K, because they simply change the speed at which a reaction takes place, and they lower things like activation energy. The concentrations of species with or without a catalyst will remain constant.
by Griffin G
Mon Jan 11, 2021 3:18 pm
Forum: Ideal Gases
Topic: Pressure and partial pressure
Replies: 12
Views: 62

Re: Pressure and partial pressure

Partial pressure is the pressure a specific gaseous species is responsible for contributing to the total pressure of a system.
by Griffin G
Mon Jan 11, 2021 3:17 pm
Forum: Ideal Gases
Topic: Gas constant R
Replies: 26
Views: 135

Re: Gas constant R

R is the universal gas constant. It will be given on exams as a part of the constants and equations sheet. Lavelle doesn't expect us to memorize it.
by Griffin G
Thu Dec 17, 2020 1:51 am
Forum: Polyprotic Acids & Bases
Topic: Defintion
Replies: 24
Views: 798

Re: Defintion

Mauricio Maravilla 3C wrote:If it can accept more than one proton

If it's a base^^. If an acid is polyprotic, it can give up 2+ protons.
by Griffin G
Thu Dec 17, 2020 1:50 am
Forum: Polyprotic Acids & Bases
Topic: Defintion
Replies: 24
Views: 798

Re: Defintion

A base or acid is polyprotic when it can surrender (acid) or accept (base) more than one proton. For example, H2SO4 can become HSO4^- which can become SO4^2-.
by Griffin G
Thu Dec 17, 2020 1:48 am
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Why isn't HF a strong acid?
Replies: 23
Views: 150

Re: Why isn't HF a strong acid?

HF isn't a strong acid because F bonds so tightly to H, that it is hard to get the two to separate. It's still a super dangerous compound though.
by Griffin G
Thu Dec 17, 2020 1:46 am
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Stronger acids and stability?
Replies: 5
Views: 69

Re: Stronger acids and stability?

Strong acids want to give up their proton more willingly. So, I suppose its possible to say that weak acids have a more stable structure because they are less willing to surrender a proton.
by Griffin G
Thu Dec 17, 2020 1:45 am
Forum: Amphoteric Compounds
Topic: More likely acid or base
Replies: 4
Views: 47

Re: More likely acid or base

Amphoteric compounds rely on their environment. So, if there is a more common environment for a chemical to exist in then yes it can be considered to most likely act basic or acidic.
by Griffin G
Sun Dec 06, 2020 8:18 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: tetradentate
Replies: 8
Views: 73

Re: tetradentate

I'm pretty sure dentate literally means "teeth" in French. In this context, it means how many sites a molecule has that can bind to the metal ion in a coordination compound.
by Griffin G
Sun Dec 06, 2020 8:16 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination Number
Replies: 13
Views: 125

Re: Coordination Number

A coordination number is basically the amount of bonds the metal ion has with ligands.
by Griffin G
Sun Dec 06, 2020 8:14 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Identifying Ligands
Replies: 3
Views: 18

Re: Identifying Ligands

Ligands are the molecules found in the brackets, or a coordination sphere, of a coordination compound. They are basically just the things that are directly connected to the metal ion. If a ligand is present, I suppose that just implies that you are working with a coordination compound.
by Griffin G
Sun Dec 06, 2020 8:12 pm
Forum: Biological Examples
Topic: Most abundant coordination compound question
Replies: 2
Views: 38

Re: Most abundant coordination compound question

Most coordiantion compounds are either created by humans, or produced by organisms. So as the other commentor stated, heme is probably the most abundant considering how many organisms rely on it and how much each organism produces.
by Griffin G
Sun Dec 06, 2020 8:11 pm
Forum: Biological Examples
Topic: Complex Ion Biological Importance
Replies: 3
Views: 47

Re: Complex Ion Biological Importance

They can have numerous biological applications! Complex ions are used by your body naturally, can be used as medication, etc. etc.
by Griffin G
Sun Nov 29, 2020 11:58 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: H2O VSEPR
Replies: 27
Views: 155

Re: H2O VSEPR

H2O is bent, because of the 2 lone pairs on the oxygen.
by Griffin G
Sun Nov 29, 2020 11:57 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Determining Type of Bond from Shape
Replies: 12
Views: 59

Re: Determining Type of Bond from Shape

Unfortunately, shape alone wouldn't give you enough information. You would also need to know the lewis structure.
by Griffin G
Sun Nov 29, 2020 11:55 pm
Forum: Hybridization
Topic: Delocalized Pi Bond
Replies: 10
Views: 94

Re: Delocalized Pi Bond

A delocalized pi bond is when there are multiple resonance structures for a molecule, and they include double bonds that are in different positions. You could recognize this in a structure like benzene with rings.
by Griffin G
Sun Nov 29, 2020 11:54 pm
Forum: Hybridization
Topic: Determining the number of sigma and pi bonds
Replies: 8
Views: 57

Re: Determining the number of sigma and pi bonds

Yes. Count all the bonds, and thats the number of sigma bonds. Then count the additional bonds in double or triple bonds and that's the number of pi bonds.
by Griffin G
Sun Nov 29, 2020 11:52 pm
Forum: Biological Examples
Topic: Cisplatin Bonding
Replies: 4
Views: 27

Re: Cisplatin Bonding

I'm pretty sure the only place it can bond to in a dna strand is two guanines, and that's why Lavelle named it something-to-do-with-guanine inhibitor.
by Griffin G
Sun Nov 22, 2020 7:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Linear Strucutres
Replies: 6
Views: 29

Re: Linear Strucutres

The ONLY angle found would be 180.
by Griffin G
Sun Nov 22, 2020 7:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pairs
Replies: 6
Views: 43

Re: Lone Pairs

Lone pairs have a larger region of electron density associated with them, because they are only being pulled towards one atom, rather than "stretched" between two. This gives them the ability to "diffuse" through space more than bonding electrons.
by Griffin G
Sun Nov 22, 2020 7:50 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Axial and Equatorial atoms
Replies: 6
Views: 35

Re: Axial and Equatorial atoms

I also had this same question. I believe that axial atoms are ones that form about a 90º angle; equatorial atoms are ones that form an angle smaller than 90º. However, what I'm confused on is whether the angle is to the central atom or to another molecule. I believe the angle is to other atoms surr...
by Griffin G
Sun Nov 15, 2020 10:24 pm
Forum: Bond Lengths & Energies
Topic: Hydrogen Bonds
Replies: 16
Views: 160

Re: Hydrogen Bonds

No. H-H, is not a hydrogen bond. It's just a normal bond between two hydrogens.
by Griffin G
Sun Nov 15, 2020 10:21 pm
Forum: Bond Lengths & Energies
Topic: Valence electrons of nitrogen
Replies: 10
Views: 57

Re: Valence electrons of nitrogen

He meant that in its lowest energy state, nitrogen has 8 electrons, a complete octet. When not part of a compound, nitrogen has only 5 electrons in the valence shell.
by Griffin G
Sun Nov 15, 2020 10:19 pm
Forum: Electronegativity
Topic: Zeff and Shielding
Replies: 3
Views: 16

Re: Zeff and Shielding

Zeff refers to the effective nuclear charge. If you are trying to calculate the charge the nucleus has on the valence electrons, you need to consider A how many protons there are and B how many other electrons there are between the valence electrons and the nucleus. These electrons are "shieldi...
by Griffin G
Sun Nov 15, 2020 10:15 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: lodon dispersion forces
Replies: 8
Views: 17

Re: lodon dispersion forces

They aren't a bond, but they are an intermolecular force. They're the weakest because they only exist thanks to induced dipole-induced dipole interactions, which are inherently weak, if you compare them to any other interactions.
by Griffin G
Sun Nov 08, 2020 10:32 pm
Forum: Formal Charge and Oxidation Numbers
Topic: formal charge
Replies: 11
Views: 44

Re: formal charge

Yes.
by Griffin G
Sun Nov 08, 2020 10:31 pm
Forum: Octet Exceptions
Topic: Identifying Radicals
Replies: 24
Views: 202

Re: Identifying Radicals

If you're drawing a lewis structure and notice there's a single lonely unpaired electron.
by Griffin G
Sun Nov 08, 2020 10:30 pm
Forum: Octet Exceptions
Topic: Expanded Octets
Replies: 6
Views: 27

Re: Expanded Octets

Elements in the 3rd row and beyond that use d-orbitals can do some funky stuff and have expanded octets.
by Griffin G
Sun Nov 08, 2020 10:28 pm
Forum: Resonance Structures
Topic: Valence Electrons [ENDORSED]
Replies: 43
Views: 383

The number of valence electrons does have to do with which group, generally. This is true for elements that aren't in the middle chunk of the periodic table.
by Griffin G
Sun Nov 08, 2020 10:25 pm
Forum: Resonance Structures
Topic: Delocalized Electrons
Replies: 3
Views: 15

Re: Delocalized Electrons

Delocalized meaning the electrons aren't involved in just one bond between two atoms, but that the electron density clouds are involved in multiple places throughout the molecule.
by Griffin G
Sun Nov 01, 2020 11:30 pm
Forum: Properties of Light
Topic: Wavelenght
Replies: 17
Views: 116

Re: Wavelenght

No they have the shortest wavelength.
by Griffin G
Sun Nov 01, 2020 11:28 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: h vs. ħ?
Replies: 11
Views: 153

Re: h vs. ħ?

ħ, or h bar is simply h/2pi. h as you know is plancks constant. h bar exists just to save space. So (1/2)ħ is the same as h/4pi.
by Griffin G
Sun Nov 01, 2020 11:26 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: The equation
Replies: 7
Views: 96

Re: The equation

We know we have to use the Heisenberg equation when we are asked for uncertainty in momentum or position. When given states of an electron we would probably be asked to use the Rydberg equation, like you described.
by Griffin G
Sun Nov 01, 2020 11:23 pm
Forum: Trends in The Periodic Table
Topic: positive and negative ion
Replies: 14
Views: 87

Re: positive and negative ion

Anions have a larger atomic radius than cations, because the added electron decreases the net charge of the nucleus, i believe.
by Griffin G
Sun Nov 01, 2020 11:21 pm
Forum: Lewis Structures
Topic: Brackets for Anions
Replies: 6
Views: 74

Brackets for Anions

I noticed that when an anion is formed in a lewis dot structure, they get a bracket around the chemical symbol with 8 electrons shown as their new octet. Are we supposed to only use brackets in lewis structures for anions or do other species get them too?
by Griffin G
Sun Oct 25, 2020 10:26 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: h/4pi
Replies: 7
Views: 74

Re: h/4pi

This is, more than anything, a convention. We could set some random letter to equal h/4pi, but regardless you'd have to plug h/4pi into your calculator each time, because pi is an irrational number. You COULD simply memorize a simplified version of h/4pi, but then your answers would lose accuracy.
by Griffin G
Sun Oct 25, 2020 10:24 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: orbital concepts
Replies: 6
Views: 66

Re: orbital concepts

Orbitals are regions of space where it is likely for an electron to be found. This concept is somewhat confusing, because electrons have both wave and particle like properties. So, you can think of orbitals as regions where an electron exists. Also, yes there are more hypothetical orbitals above f, ...
by Griffin G
Sun Oct 25, 2020 10:20 pm
Forum: Properties of Light
Topic: Speed of light
Replies: 25
Views: 163

Re: Speed of light

For this class, I would use 2.99792 x 10^8 m.s^-1 because that is the value given on the constants and equations worksheet Lavelle sent in an email. However, whatever value you use just depends on how accurate you want to be.
by Griffin G
Sun Oct 25, 2020 10:16 pm
Forum: Balancing Chemical Reactions
Topic: States of matter in chem equations
Replies: 13
Views: 148

Re: States of matter in chem equations

I believe that when the information of state is given, it is best practice to include it in your balanced equation. Otherwise, I don't think we need to include the state (unless we are for some reason given sufficient information such as temperature and pressure to determine state).
by Griffin G
Sun Oct 25, 2020 10:13 pm
Forum: Photoelectric Effect
Topic: Frequency and energy
Replies: 15
Views: 79

Re: Frequency and energy

Yes!
The equation E=hv shows that as frequency (v) increases, so does E (energy). The h is Planck's constant.
by Griffin G
Sun Oct 18, 2020 10:18 pm
Forum: Photoelectric Effect
Topic: In a Vacuum
Replies: 7
Views: 38

Re: In a Vacuum

The vacuum is only necessary to remove as many variables from an experiment as possible. If electrons interacted with molecules in the air, they would lose energy, bounce in different directions, etc. That is to say - a vacuum is used to collect the most accurate scientific data possible, the photoe...
by Griffin G
Sun Oct 18, 2020 10:16 pm
Forum: Properties of Light
Topic: Light as a wave
Replies: 3
Views: 62

Re: Light as a wave

This is why particle/wave duality is so funky! Light has properties of both waves AND particles (as do all things), which is why we observe that an increase in intensity is not the same as an increase in energy (decrease in wavelength). If light solely had the properties of a wave, then yes an incre...
by Griffin G
Sun Oct 18, 2020 10:13 pm
Forum: Properties of Light
Topic: Intensity v Energy
Replies: 18
Views: 167

Re: Intensity v Energy

Hi!
In this context of the lecture, intensity means the amount of photons being fired at a surface, and the energy referred to how much energy each individual photon possesses.
by Griffin G
Sun Oct 18, 2020 10:10 pm
Forum: Properties of Electrons
Topic: Electrons Excited or Ejected
Replies: 19
Views: 145

Re: Electrons Excited or Ejected

Hello! The ejection of an electron is when it gains so much energy it leaves an atom altogether. You could also think of this as the electron being excited to the infinite energy level. Exciting an electron is when you give an electron some energy, and it jumps up energy level(s) within the orbit of...
by Griffin G
Sun Oct 18, 2020 10:07 pm
Forum: Properties of Electrons
Topic: Ionizing Electrons vs Ejecting Electrons
Replies: 6
Views: 47

Re: Ionizing Electrons vs Ejecting Electrons

Hello! While it is possible to ionize an atom by ejecting an electron, it isn't possible to ionize an electron itself. Ionization specifically refers to changing the charge of an atom or molecule in a specific way. An electron's negative charge is static. I believe you may have misheard or misunders...
by Griffin G
Sun Oct 11, 2020 5:12 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Moles vs molecules
Replies: 14
Views: 182

Re: Moles vs molecules

A mole is just an amount. If you wanted to, you could have a "mole of moles", however that many moles would form a planet larger than earth. Here's a youtube video https://www.youtube.com/watch?v=SvtMl-V4Uv4&ab_channel=DanielChevy . Moles are just a unit we use to quantify large number...
by Griffin G
Sun Oct 11, 2020 5:07 pm
Forum: Balancing Chemical Reactions
Topic: Whole Number Stoichiometric Coefficients
Replies: 12
Views: 108

Re: Whole Number Stoichiometric Coefficients

Technically yes it would still be mathematically correct from the surface level. However, if you think about the situation logically, you will realize it's impossible to have half an atom (in that regard), or to just split a molecule down the middle. So, while the math is basically correct, non-whol...
by Griffin G
Sun Oct 11, 2020 5:04 pm
Forum: Limiting Reactant Calculations
Topic: Determining Solution Concentration
Replies: 3
Views: 51

Re: Determining Solution Concentration

Yes! M = molarity, n = moles, and v = volume (in liters). If you're given some other unit of volume, it would be best to convert it into liters, but you can still use the same formula regardless.
by Griffin G
Sun Oct 11, 2020 5:01 pm
Forum: Balancing Chemical Reactions
Topic: States of Molecules
Replies: 9
Views: 125

Re: States of Molecules

The state of a molecule isn't a requirement to be included when balancing equations, because it doesn't alter the ratio of atoms in any way. However, if we are given the information then it would be a good idea to include as much detail as possible, for practice, but that's up to you.
by Griffin G
Fri Oct 09, 2020 8:57 am
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: precision for molar masses
Replies: 14
Views: 115

Re: precision for molar masses

Personally, when using set values like molecular weight, I don't round at all until the very end, and then I round to the sigfigs of the experimentally recorded data (like grams of reagent). On exams we will all be given identical periodic tables, and I think it would be best to use the complete val...

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