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by Brittany Tran 3I
Thu Dec 05, 2019 4:30 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: 6C.21
Replies: 2
Views: 150

Re: 6C.21

the anion for formic acid (HCOO-) also exhibits resonance, so it's more stable than the anion for acetic acid (CH3COO-). since the anion is more stable, formic acid is slightly stronger
by Brittany Tran 3I
Thu Dec 05, 2019 2:12 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Polydentate Ligands
Replies: 2
Views: 63

Re: Polydentate Ligands

you can usually tell if a ligand is polydentate if it has lone pairs that are available to form coordinate covalent bonds. it should also be able to bend in a way that will allow it to bind to two different sites on a transition metal atom. the most common polydentate ligands we should know are oxal...
by Brittany Tran 3I
Thu Dec 05, 2019 2:10 pm
Forum: Biological Examples
Topic: Biological Significance
Replies: 2
Views: 71

Re: Biological Significance

we should know the biological importance of hemoglobin, myoglobin, cisplatin, Cr, Co, Zn, Mn, Ni, and Cu
by Brittany Tran 3I
Thu Dec 05, 2019 2:08 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 9
Views: 266

Re: Cisplatin

cisplatin has two chlorine atoms next to each other, so it can bind to two guanines at a time. the nitrogen in the guanine displaces the chlorines in cisplatin, so cisplatin can bind to the guanine. this stops dna replication
by Brittany Tran 3I
Thu Dec 05, 2019 1:41 pm
Forum: Industrial Examples
Topic: What do we need to know?
Replies: 15
Views: 315

Re: What do we need to know?

i think we need to know the structures and functions of hemoglobin, myoglobin, vitamin b12, cisplatin, and transplatin
by Brittany Tran 3I
Tue Nov 26, 2019 8:53 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Cis vs Trans
Replies: 21
Views: 482

Re: Cis vs Trans

cis molecules have groups on the same side of the molecule, and trans molecules have groups on different sides of the molecule. usually, cis molecules are polar and trans molecules are nonpolar
by Brittany Tran 3I
Tue Nov 26, 2019 8:51 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number vs. Coordination Number
Replies: 8
Views: 143

Re: Oxidation Number vs. Coordination Number

oxidation number is the charge on the ion. coordination number is the number of covalent bonds connecting the central ion to the ligands in a coordination compound
by Brittany Tran 3I
Tue Nov 26, 2019 8:49 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: brackets
Replies: 13
Views: 145

Re: brackets

brackets signify the atoms and ligands in the coordination compound
by Brittany Tran 3I
Tue Nov 26, 2019 8:48 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelate
Replies: 3
Views: 48

Re: Chelate

a chelate is just a complex with ligands that form a ring that includes the central metal atom or ion. only polydentate ligands can form chelates
by Brittany Tran 3I
Tue Nov 26, 2019 8:46 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Summary for Naming Coordination Compounds
Replies: 3
Views: 60

Re: Summary for Naming Coordination Compounds

the ligands are listed first in alphabetical order, and the Greek prefixes (di-, tri-, tetra-, penta-) before the ligands are based on how many ligands there are. then you list the name of the metal with the oxidation state in parentheses. if the charge of the complex is negative overall, then you a...
by Brittany Tran 3I
Tue Nov 19, 2019 11:31 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity
Replies: 5
Views: 47

Re: Polarity

GaF3 is nonpolar since it's symmetrical. the individual dipole moments cancel out, so the molecule doesn't have a net dipole. the double bond doesn't matter when determining polarity
by Brittany Tran 3I
Tue Nov 19, 2019 11:29 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Ionic Bonds
Replies: 4
Views: 46

Re: Ionic Bonds

ionic bonds generally happen between metals and nonmetals. they don't have to be restricted to alkali metals
by Brittany Tran 3I
Tue Nov 19, 2019 11:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Difference between Electorn arrangement and VSEPR
Replies: 5
Views: 103

Re: Difference between Electorn arrangement and VSEPR

finding the VSEPR model is just finding the shape of a molecule, while electron configuration is used for electrons in an atom. tetrahedral and trigonal pyramidal shapes are different. they both have four electron densities surrounding the central atom, but trigonal pyramidal molecules have one lone...
by Brittany Tran 3I
Tue Nov 19, 2019 11:26 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Instantaneous Dipole Moment
Replies: 4
Views: 50

Re: Instantaneous Dipole Moment

Since the electrons in an electron cloud are constantly moving, an instantaneous dipole moment can occur if the electrons are concentrated in one region at any given time. This can result in an unequal charge distribution and a temporary dipole moment in the molecule, which can induce temporary dipo...
by Brittany Tran 3I
Tue Nov 19, 2019 11:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angles
Replies: 3
Views: 44

Re: Bond angles

there will be a 180 degree bond angle for the C-C-N bond since the central C has two electron densities surrounding it
by Brittany Tran 3I
Thu Nov 14, 2019 10:33 am
Forum: Sigma & Pi Bonds
Topic: Triple bond?
Replies: 18
Views: 788

Re: Triple bond?

a triple bond has one sigma bond and two pi bonds
by Brittany Tran 3I
Thu Nov 14, 2019 10:31 am
Forum: Sigma & Pi Bonds
Topic: Quantum Numbers
Replies: 9
Views: 135

Re: Quantum Numbers

ml describes the orientation of the molecule around an axis, and it can range from -l to +l
by Brittany Tran 3I
Thu Nov 14, 2019 10:30 am
Forum: Sigma & Pi Bonds
Topic: Sigma and Pi Bonds
Replies: 8
Views: 111

Re: Sigma and Pi Bonds

pi bonds are also only found in double and triple bonds while sigma bonds are found in single, double, and triple bonds
by Brittany Tran 3I
Thu Nov 14, 2019 10:29 am
Forum: Sigma & Pi Bonds
Topic: Recognizing Sigma and Pi bonds
Replies: 4
Views: 65

Re: Recognizing Sigma and Pi bonds

you can just draw the Lewis structure to find the number of single, double, and triple bonds. single bonds are sigma bonds, double bonds have one sigma bond and one pi bond, and triple bonds have one sigma bond and two pi bonds
by Brittany Tran 3I
Thu Nov 14, 2019 10:27 am
Forum: Sigma & Pi Bonds
Topic: Drawing
Replies: 6
Views: 67

Re: Drawing

we won't have to draw the shapes of molecules but we have to be able to identify the shape when given the molecular formula
by Brittany Tran 3I
Tue Nov 05, 2019 7:38 pm
Forum: Octet Exceptions
Topic: Lewis Acids and Bases?
Replies: 11
Views: 150

Re: Lewis Acids and Bases?

Lewis acids and bases involve coordinate covalent bonds, in which two atoms share a pair of electrons but both of the electrons come from one atom. Lewis acids are electron pair acceptors and Lewis bases are electron pair donors
by Brittany Tran 3I
Tue Nov 05, 2019 7:36 pm
Forum: Octet Exceptions
Topic: elements in 3p block
Replies: 8
Views: 261

Re: elements in 3p block

period 3 elements can utilize their 3d orbital to form expanded octets, but the 3d orbital doesn't have to be occupied, like in the case of P, S, and Cl
by Brittany Tran 3I
Tue Nov 05, 2019 7:34 pm
Forum: Octet Exceptions
Topic: free radicals
Replies: 1
Views: 40

Re: free radicals

any molecule with an odd number valence electrons will have a radical
by Brittany Tran 3I
Tue Nov 05, 2019 7:34 pm
Forum: Octet Exceptions
Topic: Radicals
Replies: 2
Views: 67

Re: Radicals

the electrons will be drawn towards the more electronegative element, so in this case the lone electron should go on Cl
by Brittany Tran 3I
Tue Nov 05, 2019 5:56 pm
Forum: Coordinate Covalent Bonds
Topic: Single, double, and triple bonds
Replies: 6
Views: 76

Re: Single, double, and triple bonds

the bonds will have different lengths depending on the size of the elements
by Brittany Tran 3I
Wed Oct 30, 2019 9:36 pm
Forum: Ionic & Covalent Bonds
Topic: Self-test 2A.1B
Replies: 1
Views: 39

Re: Self-test 2A.1B

a) [Ar] 3d^5
b) [Xe] 4f^14 5d^10, but i don't think we need to write electron configurations for elements with f electrons
by Brittany Tran 3I
Wed Oct 30, 2019 9:34 pm
Forum: Ionic & Covalent Bonds
Topic: ionic vs covalent bonds
Replies: 6
Views: 82

Re: ionic vs covalent bonds

if the elements in the compound have an electronegativity difference higher than 2, its considered ionic. if the elements have an electronegativity difference less than 1.5, its considered covalent. we can't really determine it when the difference is between 1.5 and 2
by Brittany Tran 3I
Wed Oct 30, 2019 9:32 pm
Forum: Ionic & Covalent Bonds
Topic: Octet Rule
Replies: 8
Views: 108

Re: Octet Rule

elements in the 3rd period on have expanded octets but P, S, and Cl are the most important ones to remember
by Brittany Tran 3I
Wed Oct 30, 2019 9:30 pm
Forum: Ionic & Covalent Bonds
Topic: Homework 2A.11
Replies: 2
Views: 37

Re: Homework 2A.11

for a, the answer is Co since it loses 2 4s electrons and 1 3d electron to become Co(3+), so its electron configuration becomes [Ar] 3d^6. you can use similar reasoning for part b
by Brittany Tran 3I
Wed Oct 30, 2019 9:25 pm
Forum: Ionic & Covalent Bonds
Topic: Partial charge
Replies: 4
Views: 50

Re: Partial charge

covalent compounds have partial charges since some elements in the compound have higher electronegativity than the others
by Brittany Tran 3I
Wed Oct 23, 2019 3:16 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Spin
Replies: 8
Views: 95

Re: Electron Spin

Electron spins are paired when they're in the same orbital, and they're parallel when they're in different orbitals
by Brittany Tran 3I
Wed Oct 23, 2019 3:11 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Atomic Radius
Replies: 18
Views: 173

Re: Atomic Radius

I don't think we need to calculate atomic radius directly, but it's defined as half the distance between the centers of two neighboring atoms
by Brittany Tran 3I
Wed Oct 23, 2019 3:07 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Exceptions to Electron Configurations
Replies: 3
Views: 49

Re: Exceptions to Electron Configurations

One s electron moves to the d orbital to make the d orbital either half filled or completely filled, which is more stable and has less energy than the expected configuration with two s electrons.
by Brittany Tran 3I
Wed Oct 23, 2019 3:01 pm
Forum: Trends in The Periodic Table
Topic: Shielding
Replies: 8
Views: 223

Re: Shielding

Inner electrons can shield valence electrons from the inward pull of the nucleus because of the electron-electron repulsion between these inner electrons and valence electrons. The valence electrons experience a weaker effective nuclear charge, making it easier to remove the electron from the atom, ...
by Brittany Tran 3I
Wed Oct 23, 2019 2:56 pm
Forum: Trends in The Periodic Table
Topic: Electron affinity
Replies: 5
Views: 45

Re: Electron affinity

Electron affinity is highest in the top right corner of the PT since these elements have shells that are nearly full, so they need less electrons to complete an octet versus elements towards the bottom left corner of the PT. For example, fluorine has 7 valence electrons and only needs one more elect...
by Brittany Tran 3I
Fri Oct 18, 2019 4:16 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Hund's Rule
Replies: 4
Views: 56

Re: Hund's Rule

electrons in the same subshell are degenerate, so they have the same energy
by Brittany Tran 3I
Fri Oct 18, 2019 4:14 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Spin State
Replies: 17
Views: 148

Re: Spin State

the positive and negative values are arbitrary. generally, the electron with +1/2 will be the arrow that's pointed upwards, and the electron with -1/2 will be the arrow that's pointed downwards, just for notation
by Brittany Tran 3I
Fri Oct 18, 2019 4:13 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: writing electron configurations?
Replies: 4
Views: 46

Re: writing electron configurations?

you can just follow the order of the elements on the periodic table to find electron configurations. if an element is in the s-block, the s orbital will be filled first. if the element is in the p-block, the s orbital is filled first, then the p orbital is filled.
by Brittany Tran 3I
Fri Oct 18, 2019 4:10 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Electron configuration with s and d subshells
Replies: 4
Views: 51

Re: Electron configuration with s and d subshells

After the 4s orbital is filled and at least one electron is in a 3d orbital, then the 3d orbitals have a lower energy than the 4s orbital. It's like this just because it corresponds with experimental observations.
by Brittany Tran 3I
Fri Oct 18, 2019 4:07 pm
Forum: Quantum Numbers and The H-Atom
Topic: Quantum vs Classical
Replies: 5
Views: 98

Re: Quantum vs Classical

In classical mechanics, electrons would be able to absorb or lose any amount of energy, which is incorrect. In quantum mechanics, electrons have both wave properties and particle properties. They are only able to absorb or lose energy in discrete amounts in order to move between energy levels. Discr...
by Brittany Tran 3I
Fri Oct 11, 2019 5:03 pm
Forum: Properties of Light
Topic: Photoelectric effect- post assessment question #34
Replies: 1
Views: 25

Re: Photoelectric effect- post assessment question #34

You can use the equation "energy of radiation - threshold energy = kinetic energy of emitted electron" to solve this equation. For energy of radiation, you can change the equation E=hv to E=hc/wavelength, since you're given wavelength in this problem. You use Planck's constant for h, speed...
by Brittany Tran 3I
Fri Oct 11, 2019 4:57 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Homework Question 1B.9
Replies: 2
Views: 72

Re: Homework Question 1B.9

You can find the energy emitted with 2.0 s * (32 J/s) = 64 J. Then, you can find energy per photon by using the equation E = hc/wavelength. Then just divide total energy emitted by energy per photon, and you'll get the number of photons of violet light that the lamp can generate in 2.0 seconds. To f...
by Brittany Tran 3I
Tue Oct 08, 2019 6:05 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: The relationship of precision between position and momentum
Replies: 3
Views: 46

Re: The relationship of precision between position and momentum

for the heisenberg indeterminacy principle, momentum and position are inversely related since uncertainty of position * uncertainty of momentum equal a constant. so as certainty of position increases, certainty of momentum decreases, and vice versa
by Brittany Tran 3I
Tue Oct 08, 2019 5:58 pm
Forum: DeBroglie Equation
Topic: How to know which equation to use
Replies: 9
Views: 200

Re: How to know which equation to use

the equation v=c/wavelength is used to find frequency, not velocity. you can use v=h/(mass*wavelength) to find velocity, depending on the specific question
by Brittany Tran 3I
Tue Oct 08, 2019 5:56 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Rydberg equation [ENDORSED]
Replies: 73
Views: 3741

Re: Rydberg equation [ENDORSED]

that's a different equation. the rydberg equation can be used to calculate wavelength or frequency of an electron when it moves to a different energy level
by Brittany Tran 3I
Thu Oct 03, 2019 9:52 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Question on F.1 Part B
Replies: 3
Views: 72

Re: Question on F.1 Part B

1 mol of C10H16O has 10 moles of carbon, 16 moles of hydrogen, and 1 mole of oxygen, so you don't need to use Avogadro's number.
by Brittany Tran 3I
Thu Oct 03, 2019 9:48 pm
Forum: Molarity, Solutions, Dilutions
Topic: textbook problem G.25
Replies: 3
Views: 74

Re: textbook problem G.25

Why are you supposed to set the final equation to 1 molecule?
by Brittany Tran 3I
Thu Oct 03, 2019 9:45 pm
Forum: Molarity, Solutions, Dilutions
Topic: G. 25
Replies: 3
Views: 86

G. 25

Practitioners of the branch of alternative medicine known as homeopathy claim that very dilute solutions of substances can have an effect. Is the claim plausible? To explore this question, suppose that you prepare a solution of a supposedly active sub- stance, X, with a molar concentration of 0.10 m...
by Brittany Tran 3I
Mon Sep 30, 2019 5:06 pm
Forum: Empirical & Molecular Formulas
Topic: HW Question L.39 - What in the world is a crucible you guys?
Replies: 3
Views: 168

Re: HW Question L.39 - What in the world is a crucible you guys?

A crucible is a vessel that you can use to perform chemical reactions. To find the empirical formula, you have to find the mass of the two reactants (tin and oxygen). To find the mass of oxygen, you can find the mass of the product (28.35 g - 26.45 g = 1.90 g) and subtract the mass of tin from that ...
by Brittany Tran 3I
Mon Sep 30, 2019 4:51 pm
Forum: Balancing Chemical Reactions
Topic: Fundamentals L, #35
Replies: 3
Views: 61

Re: Fundamentals L, #35

the balanced equation should be Fe3Br8 + 4Na2CO3 -> 8NaBr + 4CO2 + Fe3O4

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