Search found 27 matches

by Lily Emerson 1I
Wed Jun 13, 2018 11:31 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: French Toast Number 27 Part B
Replies: 4
Views: 242

Re: French Toast Number 27 Part B

you just need to do 14-(-log(1.1)) since you already know that the concentration of the new mixture is .55 - just multiply that by 2 moles of HO- to get the concentration
by Lily Emerson 1I
Sun Jun 10, 2018 10:36 pm
Forum: Amphoteric Compounds
Topic: Amphoteric and amphiprotic
Replies: 6
Views: 453

Re: Amphoteric and amphiprotic

all amphoteric substances (can act as both acids and bases) are amphiprotic, but amphiprotic substances specifically can donate and accept hydrogen ions. not all acid/base reaction make use of hydrogen ion exchange
by Lily Emerson 1I
Sun Jun 10, 2018 10:29 pm
Forum: Bronsted Acids & Bases
Topic: 12.15
Replies: 1
Views: 169

Re: 12.15

Kw is a water constant, so if you know the concentration of OH- you can find the concentration of H3o+
by Lily Emerson 1I
Sun Jun 10, 2018 9:02 pm
Forum: Properties of Electrons
Topic: Wave-like Properties of Electron
Replies: 5
Views: 192

Re: Wave-like Properties of Electron

i think it's typically like 1x10^-18
by Lily Emerson 1I
Sat Jun 02, 2018 9:52 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Significance of Coordination Number?
Replies: 7
Views: 214

Re: Significance of Coordination Number?

i guess it could help with figuring out the shape of a molecule? unsure if it has any other important values that we've talked about
by Lily Emerson 1I
Sat Jun 02, 2018 9:48 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelate? [ENDORSED]
Replies: 2
Views: 94

Re: Chelate? [ENDORSED]

just a compound with two or more ligands on the central atom
by Lily Emerson 1I
Wed May 30, 2018 11:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Problem 4.9
Replies: 3
Views: 106

Problem 4.9

Why is the shape of ICl3 T-shaped instead of trigonal planar or trigonal pyramidal?
by Lily Emerson 1I
Sun May 27, 2018 11:07 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: lone pairs and polarity
Replies: 2
Views: 72

Re: lone pairs and polarity

molecules don't need to have an odd number of lone pairs to be polar (h2o only has 2 lone pairs on the oxygen), but basically the lone pairs push the electrons on the other atoms away from their atom, which makes a molecule polar
by Lily Emerson 1I
Thu May 24, 2018 8:26 am
Forum: Lewis Structures
Topic: 3.45 quick question
Replies: 3
Views: 108

Re: 3.45 quick question

nitrogen has a lower electronegativity since it's closer to the left (or further away from fluorine), so it goes in the center
by Lily Emerson 1I
Wed May 23, 2018 10:15 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal charge with ions
Replies: 4
Views: 216

Formal charge with ions

when calculating formal charges of ions, do we add/subtract the indicated charges on the atoms that they influence? or do we just use the typical number of valence electrons?
by Lily Emerson 1I
Sun May 20, 2018 11:41 pm
Forum: Ideal Gases
Topic: PV=nRT
Replies: 3
Views: 248

Re: PV=nRT

i think you might not be able to use them since PV=nRT is for gas and m1v1=m2v2 is for liquid solutions - not 100% sure though
by Lily Emerson 1I
Sun May 20, 2018 11:32 pm
Forum: Bond Lengths & Energies
Topic: Bond Length
Replies: 9
Views: 347

Re: Bond Length

I'm not sure if there's any formula for bond length (at least not one that we've covered) but generally triple bonds are shorter than double bonds which are shorter than single bonds. it has to do with the fact that when you share more electrons, they're more strongly drawn to the nuclei of the atom...
by Lily Emerson 1I
Sun May 06, 2018 11:06 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: midterm Q.7b [ENDORSED]
Replies: 3
Views: 136

Re: midterm Q.7b [ENDORSED]

the negative sign just means that bound electrons have lower energy than free electrons. the E(infinity) indicates that, since a free electron could be thought of as just being in a very far-off shell (high n value)
by Lily Emerson 1I
Sun May 06, 2018 10:56 pm
Forum: Molarity, Solutions, Dilutions
Topic: Test 1. Q7.
Replies: 1
Views: 173

Re: Test 1. Q7.

my TA told us that there wasn't enough information to answer this question, so they only checked for he amount of C and H that we found
by Lily Emerson 1I
Sun May 06, 2018 10:55 pm
Forum: General Science Questions
Topic: Solutions for tests
Replies: 3
Views: 253

Re: Solutions for tests

probably go to office hours
by Lily Emerson 1I
Sun Apr 29, 2018 8:52 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: 2.13
Replies: 3
Views: 75

Re: 2.13

the cartesian axis is just the 3D axis used to describe the shape of the orbital, like in math classes how you can draw vectors on 3D graphs. the lobe orientation is based on where the lobe lies on this axis
by Lily Emerson 1I
Sun Apr 29, 2018 8:51 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Why does 4s fill up before 3d?
Replies: 4
Views: 161

Re: Why does 4s fill up before 3d?

s, p, d, and f are short for sharp, principle, diffuse, and fundamental based on the type of spectral lines the orbitals make
by Lily Emerson 1I
Fri Apr 27, 2018 3:24 pm
Forum: DeBroglie Equation
Topic: does everything have a wavelength
Replies: 10
Views: 327

does everything have a wavelength

just kinda forgot this in my notes, but while im on the topic is there any kind of cutoff for when we really consider an object having a wavelength?
by Lily Emerson 1I
Sun Apr 22, 2018 10:15 pm
Forum: Balancing Chemical Reactions
Topic: Q4
Replies: 3
Views: 180

Re: Q4

Organic compounds pretty much alway combust into water and co2, so the balances equation is 2C13H10 + 31O2 -> 26CO2 + 10H20
by Lily Emerson 1I
Sun Apr 22, 2018 10:13 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: ∆P and ∆X
Replies: 5
Views: 204

Re: ∆P and ∆X

I find it easier to think of them more like values with margins of error, so delta P and delta X are ranges of values where the true value is somewhere in the interval.
by Lily Emerson 1I
Sun Apr 22, 2018 10:11 pm
Forum: Properties of Light
Topic: Memorizing formulas test 2
Replies: 16
Views: 534

Re: Memorizing formulas test 2

all the formulas and constants for this course were on the front cover of the last test, I don't think you have to worry about memorizing them
by Lily Emerson 1I
Sun Apr 15, 2018 8:48 pm
Forum: Photoelectric Effect
Topic: Example 1.5 in the textbook [ENDORSED]
Replies: 2
Views: 112

Re: Example 1.5 in the textbook [ENDORSED]

we divide the velocity of the electron by planck's constant to isolate the frequency (v) and then plug this frequency equation in to c=v
to find the wavelength of the radiation.
by Lily Emerson 1I
Sun Apr 15, 2018 8:42 pm
Forum: Photoelectric Effect
Topic: Kinetic Energy [ENDORSED]
Replies: 2
Views: 99

Re: Kinetic Energy [ENDORSED]

pretty much! the kinetic energy is just the energy that the electrons have from the photons after they've been knocked off the metal.
by Lily Emerson 1I
Sun Apr 15, 2018 8:41 pm
Forum: Properties of Light
Topic: Calculating the energy of a photon [ENDORSED]
Replies: 2
Views: 114

Re: Calculating the energy of a photon [ENDORSED]

h=6.626 x 10^-34, which is planck's constant. v is the frequency of blue light, which is the 6.4 x 10^14 that you'd found before
by Lily Emerson 1I
Sun Apr 08, 2018 10:23 pm
Forum: Significant Figures
Topic: Why are sig figs important?
Replies: 13
Views: 1065

Re: Why are sig figs important?

I guess sig figs are used to just so that we have a system to base our calculations off of such that we'll all get the same answer as long as we do it correctly. It limits the variation in how frequently we round and to which decimal place, which i guess helps to keep answers consistent across the b...
by Lily Emerson 1I
Sun Apr 08, 2018 10:16 pm
Forum: Empirical & Molecular Formulas
Topic: Molecular/Empirical Formulas
Replies: 2
Views: 118

Re: Molecular/Empirical Formulas

Generally carbon comes first, then hydrogen, then the remaining elements in alphabetical order.
by Lily Emerson 1I
Sun Apr 08, 2018 10:15 pm
Forum: Balancing Chemical Reactions
Topic: Balancing the Equation
Replies: 9
Views: 363

Re: Balancing the Equation

I used to write out the number of each element below the equations so that I could visualize it better and then look for common factors to balance chemical equations. You could also set up a system of equations with variable coefficients before each molecule in the reaction and balance it that way, ...

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