Search found 65 matches

by SashaAnand2J
Sun Jan 24, 2021 9:40 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Inert Gases and Le Chatelier's Principle
Replies: 6
Views: 12

Re: Inert Gases and Le Chatelier's Principle

As long as the volume of the chamber isn't changed, the inert gas does not change partial pressures involved in the reaction! By definition, inert gases do not react, so their presence does not impact equilibrium in any way (essentially the premise that they would even be a reactant is incorrect). R...
by SashaAnand2J
Sun Jan 24, 2021 9:34 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: figuring out whether salts are acidic or basic
Replies: 4
Views: 15

Re: figuring out whether salts are acidic or basic

Hi Jaden, Pulling H+ from the water simply means the base in water is producing OH-, although some bases have a hydroxide group on them, such as K(OH) and Li(OH). Remember, the typical dissociation equation for bases is: [B] + [H2O] --> [BH+] + [OH-]. This is a good representation of how the base &q...
by SashaAnand2J
Sun Jan 24, 2021 9:24 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Determining the Predominant Species
Replies: 5
Views: 28

Re: Determining the Predominant Species

Hi Elena, Sapling gives a really helpful diagram for determining predominant species, and it would be definitely worth it to screenshot/draw out the diagrams they give in the hints! For an acid: if pH < pKa - the neutral species is predominant; if pH > pKa - the charged (basic) species is predominan...
by SashaAnand2J
Sun Jan 24, 2021 9:20 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Determining Acid Dissociation
Replies: 2
Views: 15

Re: Determining Acid Dissociation

Hi Isabel! Acids or bases release an OH- or H3O+. In the homework for this week, all acids were specified as monoprotic, and bases were given as amines. This means each acid/base only produces a single OH- or H3O+ in the balanced reaction. The general dissociation equations look like: [HA] + [H2O] -...
by SashaAnand2J
Sun Jan 24, 2021 9:07 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Reversible Reaction
Replies: 5
Views: 20

Re: Reversible Reaction

Hi Nathan,
Forward enthalpy and "backward" enthalpy of a reaction are different. The arrow points in one direction to specify which direction the given enthalpy applies to. The given enthalpy would not work for the reverse reaction. I hope this helps!
by SashaAnand2J
Mon Jan 18, 2021 2:11 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K small or big
Replies: 5
Views: 24

Re: K small or big

Hi Zihan, I'm also not sure why this is the case, but I'm assuming it is because there needs to be a significant enough difference (whatever the threshold may be) for a reaction to be considered strongly-product favored or strongly-reactant favored. Any values in between these aren't extreme enough ...
by SashaAnand2J
Mon Jan 18, 2021 2:09 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE Table- What increases and what decreases
Replies: 3
Views: 14

Re: ICE Table- What increases and what decreases

Hi Eileen, Depending on what the problem is asking for, the concentration of the product or reactant may go down. Typically, whatever the reaction starts with will decrease and the compounds on the opposite side of the equation increase. For example, if an experiment begins with the reactants, this ...
by SashaAnand2J
Mon Jan 18, 2021 2:06 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Quotient
Replies: 12
Views: 423

Re: Quotient

Hi Matthew!

Q is similar to K, in that the equation setup for both are identical, however, the concentrations that are substituted into the equations are different. Q is when the concentrations of the reactant and product are not at equilibrium. K always uses equilibrium constants.
by SashaAnand2J
Mon Jan 18, 2021 2:04 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Ka and Kb relationship
Replies: 5
Views: 18

Re: Ka and Kb relationship

Hi Elena!

Ka and Kb are inversely proportional because Ka*Kb=Kw (10^-14). Because both are on the same side of this equation, one must increase if the other decreases and vice versa.
by SashaAnand2J
Mon Jan 18, 2021 2:03 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Getting two positive x values when using quadratic
Replies: 43
Views: 160

Re: Getting two positive x values when using quadratic

Hi Nicole! Although you can get two positive x values when using the quadratic equation, typically one of the values will be too large and cause a concentration to become a negative (which is not possible). In general, test out both values, but the value that keeps the concentration positive is corr...
by SashaAnand2J
Sun Jan 10, 2021 6:25 pm
Forum: Ideal Gases
Topic: partial pressures
Replies: 14
Views: 63

Re: partial pressures

Partial pressures are the molar fraction of a gas over total pressure in a container (from adding up the total moles of gas in the reaction). I believe in all of the examples concerning equilibrium, the total pressure is 1 atm.
by SashaAnand2J
Sun Jan 10, 2021 6:00 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs Kc
Replies: 9
Views: 30

Re: K vs Kc

Hi Stephanie! I am a bit confused by your question, as K is referring to an equilibrium constant and Kc simply specifies that the equation uses concentrations. Assuming you're asking how to convert between Kc and Kp, you use the formula Kp = Kc (RT) ^delta(n), where delta(n) represents moles of gas ...
by SashaAnand2J
Sun Jan 10, 2021 5:53 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Left vs. Right
Replies: 29
Views: 95

Re: Left vs. Right

The two terms are very similar. However, shift right/left is referring to a situation in which equilibrium is disturbed and the reaction quotient Q moves in the direction of K. This is Le Chatelier's principle. Saying a reaction favors the left/right is referring to the value of K itself, and whethe...
by SashaAnand2J
Sun Jan 10, 2021 5:49 pm
Forum: Ideal Gases
Topic: inert gas and pressure changes
Replies: 9
Views: 33

Re: inert gas and pressure changes

Due to Le Chatelier's principle, the equilibrium constant does not change when additional gas is added in a reaction, however, Q, or the reaction quotient does change. The reaction will then move in the direction required for Q = K. Equilibrium constants for gases vary based on temperature!
by SashaAnand2J
Sun Jan 10, 2021 5:47 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Stable Reactants and Products
Replies: 7
Views: 40

Re: Stable Reactants and Products

Hi Anna! I believe the term stability refers to concepts from 14A. Based on the chemical structure, IMFs, etc. of the reactants and products, one side of the reaction may be more favorable than the other.
by SashaAnand2J
Thu Dec 17, 2020 12:30 am
Forum: Lewis Acids & Bases
Topic: Acid and Base theories
Replies: 2
Views: 12

Re: Acid and Base theories

All three types of acid-base theories are valid, but different in scope! I believe one of the UA's mentioned this in her review session -- the definitions are more broad to less broad in the order: Lewis --> Bronsted-Lowry --> Arrhenius. This is logical since the Lewis definition simply discusses th...
by SashaAnand2J
Thu Dec 17, 2020 12:26 am
Forum: Amphoteric Compounds
Topic: Amphoteric and Amphiprotic
Replies: 2
Views: 24

Re: Amphoteric and Amphiprotic

Hi Aimee! While the definitions of amphoteric and amphiprotic are very similar, they are not identical. Note that all amphiprotic substances are amphoteric, although all amphiprotic substances may not be amphoteric. This is because amphoteric substances simply have to be able to react with acids and...
by SashaAnand2J
Thu Dec 17, 2020 12:24 am
Forum: Limiting Reactant Calculations
Topic: General Limiting Question
Replies: 9
Views: 68

Re: General Limiting Question

Hi Blake!

While the limiting reactant does determine how much product will be formed, note that this is the theoretical yield rather than the actual yield. The actual yield is almost always below the theoretical yield, since not all reactants convert into products regardless of calculations.
by SashaAnand2J
Tue Dec 15, 2020 1:12 pm
Forum: Student Social/Study Group
Topic: Study music
Replies: 32
Views: 172

Re: Study music

This sounds like an odd recommendation, but the Mario Kart Study Playlist on Spotify is my go to! Video game music helps with my concentration a lot and I would suggest listening to it if you find yourself checking your phone every 5 minutes while studying. I'm sure there's some science behind it :&...
by SashaAnand2J
Tue Dec 15, 2020 1:08 pm
Forum: Student Social/Study Group
Topic: Changing Study Habits
Replies: 35
Views: 193

Re: Changing Study Habits

I definitely think something I could have improved personally this quarter is doing the homework for the corresponding lectures as they come out. Instead of having consistent practice with the material, I used homework as a test review, while I think doing it along with lecture content each week wou...
by SashaAnand2J
Sun Dec 06, 2020 10:25 pm
Forum: Naming
Topic: Coordination Compound vs complex ion
Replies: 4
Views: 71

Re: Coordination Compound vs complex ion

Hi Rose! Complex ions are charged molecules with a central metal atom. These central atoms are attached to ligands with coordinate covalent bonds (bonds in which both electrons come from the same donor atom). On the other hand, coordination compounds are neutral molecules that have complex ions as a...
by SashaAnand2J
Sun Dec 06, 2020 10:19 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Anion Stabilization
Replies: 4
Views: 43

Re: Anion Stabilization

Hi Farah! Compounds are more stable when electrons are far apart. This means highly electronegative anions would pull lone pair electrons further away than other ions, allowing them to become delocalized.
by SashaAnand2J
Sun Dec 06, 2020 1:35 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand Types
Replies: 3
Views: 25

Re: Ligand Types

Hi Shannon! Mono/di/tri/polydentate refers to the number of regions available on a ligand to bond to a central atom. These are areas with lone pairs, for example. However, I am also confused on how to easily identify ligands and determine their type. I'm assuming drawing out the Lewis structures of ...
by SashaAnand2J
Sun Dec 06, 2020 1:31 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Sapling #3 pt. 2
Replies: 5
Views: 39

Re: Sapling #3 pt. 2

I believe coordination compounds typically have 2, 4, or 6 electron dense regions, and VSEPR shapes that align with these are the most stable for those compounds (specifically when the shape generates some form of symmetry). Seesaw is a very asymmetrical shape, so I'm assuming that is why it is less...
by SashaAnand2J
Sun Dec 06, 2020 1:15 pm
Forum: Naming
Topic: Suffixes for Ligands
Replies: 1
Views: 42

Suffixes for Ligands

Hi, I'm confused on how to name certain components of ligands. I know that iron, for example, is called ferrate, but how come in compounds like Fe(CN)6 -3, the ligand is ferricyanide and similarly, in Fe(CN)6 -4 the ligand is ferrocyanide? Will we need to know when a compound's common name and ligan...
by SashaAnand2J
Sun Nov 29, 2020 8:33 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Distinguishing Shape from # of Bonds
Replies: 3
Views: 20

Re: Distinguishing Shape from # of Bonds

Hi Meghan! From the coordinate number, I'm assuming Dr. Lavelle would want us to identify molecular geometry and not electron geometry. While electron geometry is determined by lone pairs (and we wouldn't be able to magically derive the name from steric number), the coordinate number alone is enough...
by SashaAnand2J
Sun Nov 29, 2020 8:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: ions
Replies: 8
Views: 65

Re: ions

Hi Andreas!

Charge doesn't have anything to do with VSEPR in terms of shape and molecular geometry. However, charge can influence polarity of bonds and of a molecule overall!
by SashaAnand2J
Sun Nov 29, 2020 8:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Linear Shape and Lone Pairs
Replies: 8
Views: 79

Re: Linear Shape and Lone Pairs

Hi Talia! Yes, it is possible to have a linear shape with lone pairs. Note, however, this is molecular geometry, as opposed to electron geometry! Electron geometry is directly affected by lone pairs, while molecular geometry is not. Check out this link to learn more: https://sciencing.com/difference...
by SashaAnand2J
Sun Nov 29, 2020 7:44 pm
Forum: Hybridization
Topic: Counting for Hybridization
Replies: 2
Views: 32

Counting for Hybridization

I understand that we count the number of bonding "groups" instead of individual bonds when determining hybridization, but can anyone explain why this is the case? It doesn't make sense to me intuitively that a double bond + single bond on a central atom would have the same hybridization as...
by SashaAnand2J
Sun Nov 29, 2020 7:42 pm
Forum: Hybridization
Topic: Double Bond Type
Replies: 4
Views: 43

Re: Double Bond Type

Hi Talia! A double bond can't be two pi bonds because of the type of orbital overlap required to form a bond. While sigma bonds are formed from direct end-to-end overlap, pi bonds are formed from side-by-side overlap. Sigma bonds create a stronger bond.
by SashaAnand2J
Sun Nov 22, 2020 11:41 pm
Forum: Sigma & Pi Bonds
Topic: Delocalized pi Bonds
Replies: 2
Views: 28

Re: Delocalized pi Bonds

Hi Hayden! I believe pi bonds can get delocalized as lobes overlap to form this kind of bond. This leads to electrons flowing freely between multiple atoms. I don't think this impacts the stability of the bond, since sigma bonds are direct, localized covalent bonds.
by SashaAnand2J
Sun Nov 22, 2020 11:24 pm
Forum: Hybridization
Topic: Confusion on Hybridization
Replies: 1
Views: 20

Confusion on Hybridization

I've been seeing a couple examples of hybridization where a particular molecule has more than one hybridization type, and I'm confused. How is this possible? Is there a particular rule to know when to assign which orbital/the multiple orbital types to particular bond?
by SashaAnand2J
Sun Nov 22, 2020 10:56 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: How to determine/remember molecular shape?
Replies: 4
Views: 58

Re: How to determine/remember molecular shape?

Hi! For me personally, something that has been really helpful is memorizing the different shapes and creating mnemonic devices/acronyms. Then, I practice writing the VSEPR chart with these acronyms. For example: L TP B TH TPy B TB S T L O SPy SP T L It helps more when written down, but this is my so...
by SashaAnand2J
Sun Nov 22, 2020 10:51 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Defining VSEPR Theory
Replies: 4
Views: 21

Re: Defining VSEPR Theory

VSEPR theory is a method by which we can better understand molecules' structures, which can help when scientists want to optimize reactions, for example. Molecular geometry can impact how a compound interacts with its environment. VSEPR specifically takes into account the amount of electron "cl...
by SashaAnand2J
Sun Nov 22, 2020 10:35 pm
Forum: Sigma & Pi Bonds
Topic: Sigma & Pi Bonds General Question
Replies: 2
Views: 19

Re: Sigma & Pi Bonds General Question

I would assume we will need to know the differences between sigma and pi bonds in-depth later on, but as of right now, just know that a single bond is a sigma bond, and any bonds greater than one have (n-1) pi bonds. To my knowledge, sigma bonds are directly responsible for a covalent bond, while pi...
by SashaAnand2J
Sun Nov 15, 2020 9:30 pm
Forum: Octet Exceptions
Topic: Octet Exceptions Question
Replies: 5
Views: 67

Re: Octet Exceptions Question

Expanded octets can have more than 4 bonds! You can look at phosphorous pentachloride as an example (it has 5 bonds). However, even expanded octets don't typically go beyond 5 bonds (Z=10), so don't draw an unlimited number of bonds just because the atom has d-orbitals!
by SashaAnand2J
Sun Nov 15, 2020 9:21 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: dipole moments
Replies: 10
Views: 54

Re: dipole moments

Follow Dr. Lavelle! The arrow should be pointing towards the negative dipole, because it indicates where electrons are being pulled.
by SashaAnand2J
Sun Nov 15, 2020 9:16 pm
Forum: Electronegativity
Topic: Partial vs Formal charge
Replies: 8
Views: 46

Re: Partial vs Formal charge

Partial charges are usually referred to as dipoles! This is what we are referring to when discussing dipole-ion/dipole-dipole interactions. Partial charges indicate which atom has the electrons closest or furthest away (remember electronegativity!), giving those atoms similar properties as an ion wi...
by SashaAnand2J
Sun Nov 15, 2020 9:12 pm
Forum: Lewis Structures
Topic: Bonding with Atoms in the D State
Replies: 4
Views: 13

Re: Bonding with Atoms in the D State

Hi! y=Yes, for elements with d-orbitals, you can use an expanded octet (although this usually doesn't go beyond Z=10). Using an extra lone pair would be appropriate in this case. The diagram you drew is one of the resonance structures for sulfur dioxide! The other two options are placing a formal ch...
by SashaAnand2J
Sun Nov 15, 2020 9:07 pm
Forum: Lewis Structures
Topic: Brackets
Replies: 9
Views: 52

Re: Brackets

To my understanding, enclosed brackets indicate overall charge! While certain atoms within the molecule may have their own formal charges, a bracket is placed around a complete ion's Lewis structure with its overall charge.
by SashaAnand2J
Sun Nov 08, 2020 10:02 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Covalent Bonds with Ionic Character/Polar
Replies: 3
Views: 14

Re: Covalent Bonds with Ionic Character/Polar

Covalent compounds with strong ionic character are polar covalent bonds. They are the midway point between nonpolar covalent and ionic bonds. In these types of compounds, electrons will have a "dipole moment" towards the atoms with higher electronegativity, and electrons are shared unequal...
by SashaAnand2J
Sun Nov 08, 2020 9:58 pm
Forum: Octet Exceptions
Topic: Expanded Octets
Replies: 6
Views: 27

Re: Expanded Octets

Expanded octets are possible for elements with d-orbitals! This means certain elements, such as chlorine and phosphorous, have the ability to fill electrons up to the s2p6d2 state. These typically won't go beyond 10 electrons.
by SashaAnand2J
Sun Nov 08, 2020 9:54 pm
Forum: Lewis Structures
Topic: nitrate lewis structure
Replies: 7
Views: 57

Re: nitrate lewis structure

Two oxygen double bonds doesn't work for nitrate because we want to ensure that the most stable version of the structure is being formed. Having a 5 bond nitrogen would break the octet rule, because nitrogen doesn't have a d-orbital to accommodate more valence electrons. This is why instead, a forma...
by SashaAnand2J
Sun Nov 08, 2020 9:44 pm
Forum: Electronegativity
Topic: polyatomic ions
Replies: 4
Views: 32

Re: polyatomic ions

Polyatomic ions' charges typically follow patterns based on their respective families in the periodic table, although there are exceptions depending on the bond formed. Like Mohamed mentioned, oxygen is almost always -2, unless it is bonding with one of the exceptions. Copper, iron, and a couple oth...
by SashaAnand2J
Sun Nov 08, 2020 9:22 pm
Forum: Ionic & Covalent Bonds
Topic: electron configuration
Replies: 3
Views: 25

Re: electron configuration

Hi! Orbitals are filled from lowest to highest energy levels. Although the 4s-block is technically has a higher n-value, it has a lower energy level than the 3d-block. A good trick to remember the order in which orbitals are filled (rather than memorizing) is writing a list as follows and drawing ar...
by SashaAnand2J
Sun Nov 01, 2020 10:46 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orbitals and Subshells
Replies: 3
Views: 32

Re: Orbitals and Subshells

Hi! The relationship you mentioned is flipped: orbitals are inside subshells. Orbitals are just ways to describe how electrons align/are distributed for a certain atom, but keep in mind that no one knows what electrons actually look like. Subshells and orbitals are just a mathematical/visual represe...
by SashaAnand2J
Sun Nov 01, 2020 9:50 pm
Forum: Trends in The Periodic Table
Topic: Atomic Radius of Ions
Replies: 2
Views: 48

Atomic Radius of Ions

I was wondering how to determine the atomic radius of ions that are non-isoelectronic...I'm confused as to what should be prioritized when organizing the radii in this case. For example, when comparing Na+ and Ca2+, would the high effective nuclear charge of Na+ be prioritized or the larger atomic w...
by SashaAnand2J
Sun Nov 01, 2020 9:31 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Noble Gas Configuration
Replies: 13
Views: 75

Re: Noble Gas Configuration

Either method is appropriate to represent the ground state electron configuration of noble gases, although arguably, as you mentioned, putting just the noble gas would be vague. I'm sure if a question as you mentioned came up in a test, Dr. Lavelle would specify whether to write the short-hand or co...
by SashaAnand2J
Sun Nov 01, 2020 9:27 pm
Forum: Trends in The Periodic Table
Topic: Radius trends for elements like Carbon
Replies: 4
Views: 37

Re: Radius trends for elements like Carbon

Hi Emam! If you are asking about carbon's electronegativity, carbon has a somewhat high electronegativity. It is very unlikely to lose electrons or gain electrons and create an ionic bond, although in CO2, electrons have an attraction towards oxygen, which has a higher electronegativity than carbon....
by SashaAnand2J
Sun Nov 01, 2020 9:16 pm
Forum: Trends in The Periodic Table
Topic: Isoelectronic Ions
Replies: 5
Views: 17

Re: Isoelectronic Ions

Hi Chloe! As the other comments above have mentioned, isoelectronic ions are ions with the same electron configuration, although their properties may be completely different due to their chemical composition. Something you should be aware of is that the effective nuclear charge (Z-eff) of these ions...
by SashaAnand2J
Sun Oct 25, 2020 11:14 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: N reaching infinity
Replies: 3
Views: 18

Re: N reaching infinity

The "infinity" level is theoretical! From my understanding, if the level were to reach infinity, it would just mean the electron is as far as possible from the nucleus as chemically possible, while (just barely) being a part of the atom. I would assume n=infinity could be approached, but n...
by SashaAnand2J
Sun Oct 25, 2020 9:36 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Rydberg Equation - Sapling Question 11
Replies: 1
Views: 32

Rydberg Equation - Sapling Question 11

Hi! I'm confused on this Sapling question and would appreciate some help: "A red line is observed at 656.3 nm in the spectrum of atomic hydrogen. Determine the values of n for the beginning and ending energy levels of the electron during the emission of energy that leads to this spectral line.&...
by SashaAnand2J
Sun Oct 25, 2020 9:30 pm
Forum: Einstein Equation
Topic: Sapling Homework - electron affinity
Replies: 5
Views: 88

Re: Sapling Homework - electron affinity

Yeah I couldn't get the right answer for the second part either. I wonder if there is anything wrong with my conversions. @Samantha, could you explain your steps for the first part and how you got 1.003? I used E=hc/lambda and converted nm to m as well as J to eV, but I still didn't get to 1.003. T...
by SashaAnand2J
Sun Oct 25, 2020 1:07 pm
Forum: Quantum Numbers and The H-Atom
Topic: Energy Levels
Replies: 8
Views: 83

Re: Energy Levels

Hi Will! From my understanding, photons that push electrons over the energy threshold will bounce off the metallic surface in the form of kinetic energy (refer to the work function). I'm also a little confused by your Google search, but I'm assuming that the light is absorbed while energy itself is ...
by SashaAnand2J
Sun Oct 25, 2020 1:00 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Electrons in Orbitals
Replies: 5
Views: 58

Re: Electrons in Orbitals

Hi Alen! Electrons like to fill up orbitals in order from lowest to highest energy, in terms of filling up s, p, d, f orbitals. This may be the same reason electrons fill up individual orbitals before completing pairs. Adding on to what Brianne said above, electrons are likely to take up locations t...
by SashaAnand2J
Sun Oct 18, 2020 10:04 pm
Forum: Photoelectric Effect
Topic: Short/high wavelength
Replies: 7
Views: 57

Re: Short/high wavelength

Regarding the energy threshold, you should refer to the equation E=hv, where E is energy, h is Planck's constant, and v is frequency! Wavelength is not a factor in the energy of a particular beam of light (of course it is indirectly, as frequency and wavelength are inversely proportional), and there...
by SashaAnand2J
Sun Oct 18, 2020 9:48 pm
Forum: Properties of Light
Topic: Wave properties of light
Replies: 4
Views: 58

Re: Wave properties of light

Light has a couple behaviors that demonstrate it is a wave. These are reflection, refraction, and diffraction! When in contact with new surfaces (or mediums), light interacts and changes. Crash Course Physics has a great video on this: https://www.youtube.com/watch?v=IRBfpBPELmE Also, check out this...
by SashaAnand2J
Sun Oct 18, 2020 4:43 pm
Forum: Photoelectric Effect
Topic: What happens to absorbed photons?
Replies: 6
Views: 60

Re: What happens to absorbed photons?

Hi Kushaal! You should think of photons as "packets of energy" as Dr. Lavelle mentioned in his lectures. Unlike protons, neutrons, and electrons, photons do not have a mass, but rather, are representations of energy . It would be incorrect to say the photon gets destroyed due to the First ...
by SashaAnand2J
Sun Oct 18, 2020 4:22 pm
Forum: Properties of Electrons
Topic: Work Function
Replies: 2
Views: 38

Work Function

Hi! I'm a bit confused by the work function, because the function states that E(photon) must be greater than or equal to E(remove electron). How does the "or equal to" make sense in terms of real-world application? If there is no excess energy involved when hitting a metallic surface, it w...
by SashaAnand2J
Sun Oct 18, 2020 4:07 pm
Forum: Properties of Light
Topic: Frequency vs Wavelength
Replies: 22
Views: 141

Re: Frequency vs Wavelength

Hi Brianna! Yes, frequency does have an effect on what type of wave something is, because frequency and wavelength are inversely proportional! Each wave type has a unique set of frequencies AND wavelengths that accompany it. Reference the equation c = vλ, where c is a constant ~3.0e8 meters/second. ...
by SashaAnand2J
Sat Oct 10, 2020 3:12 pm
Forum: Empirical & Molecular Formulas
Topic: Sapling Q10
Replies: 4
Views: 59

Re: Sapling Q10

Hi Ann!

Yes, you disregard the propyl magnesium bromide when calculating for Q10. We aren't concerned about the products from that reactant specifically. Just know that propyl magnesium bromide has 3 carbons to help when balancing equations!
by SashaAnand2J
Sat Oct 10, 2020 3:06 pm
Forum: Significant Figures
Topic: What Value to Use for Sig Figs
Replies: 4
Views: 25

What Value to Use for Sig Figs

I'm confused as to what value from the problem should be used as a basis for sig figs. For example, if the problem says "Given 5.9 grams of silver and 8.79 grams of gold, what is the expected yield of [some rxn]?" This obviously isn't a real question in the textbook, but I was wondering, h...
by SashaAnand2J
Wed Oct 07, 2020 2:29 pm
Forum: Empirical & Molecular Formulas
Topic: Fundamentals Problems: E9
Replies: 2
Views: 53

Fundamentals Problems: E9

Hi everyone! I am confused on the following Fundamentals problem, because while the heptahydrate component contains 7 atoms of oxygen, dry Epsom salt is just MgSO4. Should I include the heptahydrate when calculating this answer as well? E.9 Epsom salts consist of magnesium sulfate heptahydrate. Writ...
by SashaAnand2J
Tue Oct 06, 2020 8:35 pm
Forum: Balancing Chemical Reactions
Topic: State in chemical reactions
Replies: 13
Views: 117

Re: State in chemical reactions

Hi Emily! While writing down the physical state of reactants/products may not be important, knowing the physical states of these molecules is definitely helpful (especially if the question is regarding a precipitation reaction). Visualizing the reaction can help you better understand chemical proces...
by SashaAnand2J
Mon Oct 05, 2020 7:55 pm
Forum: Molarity, Solutions, Dilutions
Topic: G5 Molarity of Na
Replies: 6
Views: 95

Re: G5 Molarity of Na

Hi Adam! First, convert mass of Na2CO3 into moles. You should get 0.0199 moles Na2CO3. Next, recognize that Na+ and NaCO3 are in a 2:1 ratio (meaning there is 2 mol Na/1 mol NaCO3). If you use dimensional analysis, you should find that 2 mol Na implies 1 mol NaCO3. This means there are 0.0398 moles ...

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