Search found 58 matches

by Nare Arakelian Dis 3E
Sun Dec 08, 2019 9:34 pm
Forum: Administrative Questions and Class Announcements
Topic: 14A FInal
Replies: 6
Views: 82

Re: 14A FInal

Someone said this Friday at 5 but I am not sure how accurate that it
by Nare Arakelian Dis 3E
Sun Dec 08, 2019 9:32 pm
Forum: Student Social/Study Group
Topic: thoughts on final exam
Replies: 4
Views: 73

Re: thoughts on final exam

and also how to switch majors
by Nare Arakelian Dis 3E
Sun Dec 08, 2019 9:32 pm
Forum: Student Social/Study Group
Topic: thoughts on final exam
Replies: 4
Views: 73

Re: thoughts on final exam

Does anyone know when we will get our scores back
by Nare Arakelian Dis 3E
Sun Dec 08, 2019 9:30 pm
Forum: Administrative Questions and Class Announcements
Topic: curve
Replies: 8
Views: 100

Re: curve

I have been wondering this too. All I know is 250/500 is considered a C- and then I think he is just gonna wait to see how the final average comes out and figure out the curve then
by Nare Arakelian Dis 3E
Sun Dec 08, 2019 9:29 pm
Forum: Significant Figures
Topic: Sig Figs on Tests
Replies: 24
Views: 272

Re: Sig Figs on Tests

for pH, the number of digits after the decimal point equates to the total number of sig figs for the concentration
by Nare Arakelian Dis 3E
Sun Dec 08, 2019 3:21 pm
Forum: Calculating the pH of Salt Solutions
Topic: Titrations
Replies: 6
Views: 63

Re: Titrations

the stoichiometric point is when the moles of acid equals the moles of base, and knowing the volume and moles this can be used to calculate teh concentration and then the pH
by Nare Arakelian Dis 3E
Sun Dec 01, 2019 11:59 pm
Forum: Biological Examples
Topic: cisplatin
Replies: 3
Views: 26

Re: cisplatin

Thank you for explaining , I was confused on this topic as well
by Nare Arakelian Dis 3E
Sun Dec 01, 2019 11:51 pm
Forum: Naming
Topic: oxidation
Replies: 8
Views: 39

Re: oxidation

The oxidation number comes after the metal atom in parenthesis
by Nare Arakelian Dis 3E
Sun Dec 01, 2019 11:50 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: chelate
Replies: 5
Views: 42

Re: chelate

Does it involve ligands that are polydentates? and is cisplatin a chelate?
by Nare Arakelian Dis 3E
Sun Dec 01, 2019 11:47 pm
Forum: *Molecular Orbital Theory Applied To Transition Metals
Topic: bond order
Replies: 3
Views: 27

Re: bond order

I think just a general sense of what it means in relation to bond strength and strength. So a bond order of 3, or a triple bond, is shorter and stronger than a bond order of 2, or a double bond
by Nare Arakelian Dis 3E
Sun Dec 01, 2019 11:46 pm
Forum: *Molecular Orbital Theory Applied To Transition Metals
Topic: coordination sphere
Replies: 1
Views: 19

Re: coordination sphere

You use brackets to indicate what is inside the coordination sphere, or what is directly touching the central metal atom
by Nare Arakelian Dis 3E
Sun Nov 24, 2019 7:38 pm
Forum: Lewis Acids & Bases
Topic: Donor and Acceptor
Replies: 6
Views: 36

Re: Donor and Acceptor

I was confused on this too, thank you!
by Nare Arakelian Dis 3E
Sun Nov 24, 2019 7:31 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Intermolecular forces
Replies: 5
Views: 30

Re: Intermolecular forces

Ion- ion forces > ion-dipole forces > dipole-dipole > dipole - induced dipole > induced dipole -induced dipole. And then hydrogen bonds are basically just really strong dipole-dipole forces
by Nare Arakelian Dis 3E
Sun Nov 24, 2019 7:29 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Bond order
Replies: 5
Views: 41

Re: Bond order

A double bond has a bond order of 2, a triple bond has a bond order of 3, etc...
by Nare Arakelian Dis 3E
Sun Nov 24, 2019 7:26 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligands
Replies: 5
Views: 19

Re: Ligands

a ligand is an electron dense molecule
by Nare Arakelian Dis 3E
Sun Nov 24, 2019 7:22 pm
Forum: Sigma & Pi Bonds
Topic: Sigma and Pi Bonds
Replies: 7
Views: 39

Re: Sigma and Pi Bonds

A sigma bond is a single bond and a double bond has one sigma and one pi bond
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:50 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: regions of electron density
Replies: 10
Views: 44

Re: regions of electron density

Why is knowing the number of regions of electron density necessary when naming a molecule? The number of regions of electron density affect the shape of the molecule, but the naming of the molecule comes from only the bonded atoms, not the lone pairs. So if a molecule has 4 regions of electron dens...
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:47 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR angles
Replies: 4
Views: 34

Re: VSEPR angles

Thank you so much!
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:45 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Structure of H2O
Replies: 3
Views: 27

Re: Structure of H2O

Lauren Sanchez 3D wrote:So if there are only two areas of electron density, that is when they are opposite of each other due to the strong repulsion?


Yes, I believe so because this minimizes the repulsions by putting the lone pairs farthest away from each other
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:43 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR angles
Replies: 4
Views: 34

VSEPR angles

Does anyone have any tips or tricks for remembering the angles for each shape?
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:42 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: Hydrogen Bonding
Replies: 5
Views: 23

Hydrogen Bonding

If a molecule, like NH3 for example, has a hydrogen bonded to an electronegative element does this mean there is hydrogen bonding? or does this hydrogen then have to be bonded to another electronegative atom in order for it to be a hydrogen bond?
by Nare Arakelian Dis 3E
Sun Nov 17, 2019 2:34 pm
Forum: Hybridization
Topic: sp^3 orbital
Replies: 3
Views: 21

Re: sp^3 orbital

do we need to know this for the test?
by Nare Arakelian Dis 3E
Sun Nov 10, 2019 11:43 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polar vs covalent
Replies: 7
Views: 31

Re: Polar vs covalent

EvanWang wrote:Covalent bonds occur between two nonmentals, while ionic bonds occur between a metal and a nonmetal.



does this infer that polar and ionic are interchangeable? You have me a little confused.
by Nare Arakelian Dis 3E
Sun Nov 10, 2019 11:40 pm
Forum: Coordinate Covalent Bonds
Topic: coordinate covalent bond
Replies: 5
Views: 307

Re: coordinate covalent bond

It's a bond where both electrons come from one atom, completing the octet of an atom existing in a compound with an incomplete one. The example provided in class and in the textbook was that of boron trifluoride BF3, and boron has only six valence electrons. Its octet is completed when it forms a c...
by Nare Arakelian Dis 3E
Sun Nov 10, 2019 11:39 pm
Forum: Octet Exceptions
Topic: elements in 3p block
Replies: 8
Views: 97

Re: elements in 3p block

Thank you guys for answering! This cleared up a lot for me!
by Nare Arakelian Dis 3E
Sun Nov 10, 2019 11:39 pm
Forum: General Science Questions
Topic: Sig Figs
Replies: 7
Views: 78

Sig Figs

It's never been explicitly expressed, so I'm assuming that sig figs won't have any effect on grading on the test, but maybe I just missed when they said that. Are sig figs taken into account with points when grading?
by Nare Arakelian Dis 3E
Sun Nov 10, 2019 11:36 pm
Forum: General Science Questions
Topic: Extra Credit
Replies: 6
Views: 70

Re: Extra Credit

aww that's a bummer... we just gotta grind hard boys
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:33 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Differences between polarizing power and polarizablity
Replies: 2
Views: 31

Re: Differences between polarizing power and polarizablity

Polarizability is the ability of an atom to have a distorted electron cloud. These are usually anions, and the larger they are the more likely it is for their electrons to be on one side at a moment in time. Polarizing power is the ability of an atom to induce this dipole moment and distort the elec...
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:30 pm
Forum: Bond Lengths & Energies
Topic: Short bond lengths vs long bond lengths
Replies: 6
Views: 47

Re: Short bond lengths vs long bond lengths

Shorter bond lengths are stronger because the distance between the atoms is smaller so they are pulling more tightly on each other, leading to a stronger bond. The longer the bond length and greater the distance between the two atoms, the weaker the nuclear force is holding these atoms together and ...
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:28 pm
Forum: Octet Exceptions
Topic: Radicals
Replies: 5
Views: 46

Re: Radicals

Radicals occur when there is an odd number of valence electrons, so there will be one unpaired electron. CH3 for example has 7 valence electrons so in the lewis structure there will only be one lone electron on the carbon. I think we just have to know what they are and how to identify them. Just bec...
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:27 pm
Forum: Dipole Moments
Topic: Dipole moments on Lewis structures
Replies: 3
Views: 26

Re: Dipole moments on Lewis structures

I think just with an arrow pointing towards the molecule with the partial negative charge
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:25 pm
Forum: Lewis Structures
Topic: double bonding with halogens
Replies: 3
Views: 29

double bonding with halogens

Do the halogens like fluorine and chlorine never form double bonds in lewis structures?
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:20 pm
Forum: Octet Exceptions
Topic: elements in 3p block
Replies: 8
Views: 97

elements in 3p block

Why are Phosphorus, Chlorine, and Sulfur exceptions to the octet rule when their electron configurations do not have a 3d orbital? Is it just because they are in the third energy level?
by Nare Arakelian Dis 3E
Sun Nov 03, 2019 11:11 pm
Forum: Formal Charge and Oxidation Numbers
Topic: central atom
Replies: 21
Views: 104

central atom

Do we want to make it so that the central atom has a formal charge of zero?
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:55 pm
Forum: Octet Exceptions
Topic: More than 8 valence e-
Replies: 8
Views: 61

Re: More than 8 valence e-

Sulfur, phosphorous, and chlorine are examples of an expanded octet because starting in this row, these atoms have a d orbital which can hold extra electrons. In the normal state, they are not usually all filled so when it comes time to share electrons they are able to store more in the d orbital. H...
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:50 pm
Forum: Trends in The Periodic Table
Topic: Shielding and Electron Replusion
Replies: 3
Views: 35

Re: Shielding and Electron Replusion

They are different concepts I believe. Shielding occurs when the inner electrons block the outer electrons from the nuclear positive charge, which makes the outer electrons easier to remove. I would use this as a justification for ionization energy, but not atomic radius. Electron electron repulsion...
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:44 pm
Forum: Administrative Questions and Class Announcements
Topic: HW 4
Replies: 2
Views: 25

Re: HW 4

I think chemical bonds
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:44 pm
Forum: Bond Lengths & Energies
Topic: Double bond vs single bonds
Replies: 4
Views: 37

Re: Double bond vs single bonds

Double bond lengths are shorter than single bond lengths because double bonds are stronger, which means the force between the two atoms is going to increase, pulling them closer to each other. It would require more energy to break a double bond for this reason, because the atoms are closer together ...
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:41 pm
Forum: Ionic & Covalent Bonds
Topic: Ground State
Replies: 11
Views: 65

Re: Ground State

So if an atom's electron configuration breaks one of the rules, like Hund's rule or Pauli exclusion principle, that means it is not in ground state but in excited state
by Nare Arakelian Dis 3E
Sun Oct 27, 2019 11:38 pm
Forum: Ionic & Covalent Bonds
Topic: 4s before 3d
Replies: 4
Views: 40

Re: 4s before 3d

Why is 3d at a lower energy level than 4s?
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 10:27 pm
Forum: Trends in The Periodic Table
Topic: Study Buddies?
Replies: 8
Views: 70

Re: Study Buddies?

yess! my email is narkeli17@gmail.com
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 11:15 am
Forum: Photoelectric Effect
Topic: The Work Function
Replies: 15
Views: 90

Re: The Work Function

Is the work function the same as the ionization energy then?
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 11:06 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: More Orbital Understanding
Replies: 3
Views: 41

Re: More Orbital Understanding

For p-orbitals, for example, it is unlikely to be near the nucleus because they have a nodal plane at the nucleus which means there is zero probability of finding an electron there. Due to the fact that p-orbitals, unlike s-orbitals, have angular momentum which pushes the electron away from the nucl...
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 10:59 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Shell, Subshell, Orbital Terminology
Replies: 8
Views: 89

Re: Shell, Subshell, Orbital Terminology

So would it be correct to say that there are 3 p subshells in each shell or energy level?
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 10:51 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 4s vs. 3d
Replies: 6
Views: 35

Re: 4s vs. 3d

Why do electron-electron repulsions lead to 3d having higher energy?
by Nare Arakelian Dis 3E
Sun Oct 20, 2019 12:34 am
Forum: Trends in The Periodic Table
Topic: ionization energy
Replies: 11
Views: 326

Re: ionization energy

The problem could just be asking to compare the ionization energies of two elements and state which is larger. The energy of a photon = ionization energy plus the kinetic energy so the value of the ionization energy could also be used here for a photoelectric effect problem.
by Nare Arakelian Dis 3E
Sat Oct 12, 2019 8:49 pm
Forum: Photoelectric Effect
Topic: work function clarification
Replies: 4
Views: 31

Re: work function clarification

Are they only the same when the kinetic energy is zero? Or does this not matter
by Nare Arakelian Dis 3E
Sat Oct 12, 2019 8:38 pm
Forum: Properties of Light
Topic: Wave Properties of Electrons
Replies: 3
Views: 32

Re: Wave Properties of Electrons

I think I'm still struggling with grasping the difference between diffraction and interference. Can someone please explain?
by Nare Arakelian Dis 3E
Sat Oct 12, 2019 8:34 pm
Forum: Properties of Light
Topic: Wave Properties of electrons
Replies: 7
Views: 64

Re: Wave Properties of electrons

When waves encounter a barrier, like a wall, with small slits or openings, the waves will spread out past the openings and create these patterns as they interfere with one another. This is my understanding, I hope it helped!
by Nare Arakelian Dis 3E
Sat Oct 12, 2019 8:24 pm
Forum: Properties of Light
Topic: Diffraction and Water
Replies: 4
Views: 34

Re: Diffraction and Water

Arianna Perea 3H wrote:Are diffractions only analyzed through the peaks of waves?


I think so because in order to analyze the interference patterns, you can look at the peaks of the waves to see if they are getting narrower, larger, etc.
by Nare Arakelian Dis 3E
Sat Oct 12, 2019 8:15 pm
Forum: Properties of Light
Topic: Light intensity and Kinetic Energy
Replies: 7
Views: 72

Light intensity and Kinetic Energy

I am still kind of confused on why the kinetic energy does not change if the light intensity increases. Can someone please explain? Thanks!
by Nare Arakelian Dis 3E
Mon Oct 07, 2019 9:21 pm
Forum: Molarity, Solutions, Dilutions
Topic: G13
Replies: 2
Views: 64

G13

To prepare a fertilizer solution, a florist dilutes 1.0 L of 0.20 m NH4NO3(aq) by adding 3.0 L of water. The florist then adds 100. mL of the diluted solution to each plant. How many moles of nitrogen atoms will each plant receive? Solve this exercise without using a calculator. I used M1V1=M2V2 to ...
by Nare Arakelian Dis 3E
Thu Oct 03, 2019 11:10 pm
Forum: SI Units, Unit Conversions
Topic: Help on Fundamentals: E21
Replies: 7
Views: 101

Re: Help on Fundamentals: E21

For E21a) in particular, you're converting 0.0981 moles of Al2O3 into molecules because Al2O3 is a molecular compound. If you were dealing with an element, however, like Al, you would be converting into atoms. In both cases though, you would use Avogadro's number to convert. I was a bit confused on...
by Nare Arakelian Dis 3E
Thu Oct 03, 2019 10:58 pm
Forum: Significant Figures
Topic: subtracting with sig figs
Replies: 5
Views: 85

Re: subtracting with sig figs

So with adding and subtracting is the rule that the answer should have the same number of decimal places as the number with the least decimal places or should have the same number of sig figs overall as the number with the least number of decimal places?
by Nare Arakelian Dis 3E
Thu Oct 03, 2019 10:50 pm
Forum: Limiting Reactant Calculations
Topic: M.11
Replies: 3
Views: 84

Re: M.11

I think everything is right up until the point where you convert 0.0406 moles O2 to grams of P4010. To get 5.77 grams, I multiplied 0.0406 moles O2 ( 1 mole P4O10 / 2 moles O2) (283.89 g / 1 mole). I think you just multiplied by 2 moles of O2 instead of dividing. Hope this helps!
by Nare Arakelian Dis 3E
Thu Oct 03, 2019 8:27 pm
Forum: Empirical & Molecular Formulas
Topic: Rounding for Formulas
Replies: 8
Views: 99

Re: Rounding for Formulas

And the same applies for rounding down, right? For example, if after dividing I get 2.067 I can safely round down to 2
by Nare Arakelian Dis 3E
Thu Oct 03, 2019 8:17 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student - Part II [ENDORSED]
Replies: 130
Views: 3348

Re: Advice from a Medical Student - Part II [ENDORSED]

Thank you so much for sharing your experience! I know getting letters of recommendation is a part of the application process, and I was wondering if you had any advice on how to get close and comfortable enough with professors to ask for a letter? I am also not 100% sure I want to follow this path a...

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