Search found 50 matches

by Michelle Shin 4B
Sat Dec 07, 2019 3:02 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: relative acidity
Replies: 2
Views: 84

relative acidity

How is an anion stabilized?
by Michelle Shin 4B
Sat Dec 07, 2019 2:51 pm
Forum: Lewis Acids & Bases
Topic: neutralization
Replies: 6
Views: 152

neutralization

Can neutralization only occur between a strong acid and metal hydroxide or can it occur between weak acids and bases as well?
by Michelle Shin 4B
Sat Dec 07, 2019 2:46 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Thymine
Replies: 1
Views: 81

Thymine

What makes thymine a base?
by Michelle Shin 4B
Sat Dec 07, 2019 2:39 pm
Forum: Lewis Acids & Bases
Topic: 6A.15
Replies: 2
Views: 36

Re: 6A.15

For part a, F- would donate an electron pair (lewis base) to the PF5, which accepts the electron pair (lewis acid). Therefore, the product would be PF6-.
by Michelle Shin 4B
Sat Dec 07, 2019 2:35 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: polydentate ligands
Replies: 1
Views: 44

Re: polydentate ligands

A ligand is a polydentate if it donates at least 2 electron pairs.
by Michelle Shin 4B
Sun Dec 01, 2019 6:15 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Difference between weak acids/bases and strong acids/bases
Replies: 6
Views: 88

Re: Difference between weak acids/bases and strong acids/bases

Strong acids and bases completely ionize while weak acids and bases only partially ionize. Strong acids produce many H+ ions and strong bases produce many OH- ions.
by Michelle Shin 4B
Sun Dec 01, 2019 6:12 pm
Forum: Conjugate Acids & Bases
Topic: Acids and Bases
Replies: 3
Views: 48

Re: Acids and Bases

A conjugate acid is the species that is formed after the base accepts a proton, and a conjugate base is formed after an acid donates a proton. Bronsted acids are defined as H+ donors while Lewis acids are defined as electron pair acceptors.
by Michelle Shin 4B
Sun Dec 01, 2019 6:08 pm
Forum: Naming
Topic: Naming coordination compounds
Replies: 5
Views: 45

Naming coordination compounds

How do you determine the roman numerals when naming a coordination compound, and how do you know you need to include them in the name?
by Michelle Shin 4B
Sun Dec 01, 2019 6:03 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Ligand
Replies: 4
Views: 33

Re: Ligand

A chelate is a complex containing a ligand that forms a ring of atoms that includes the central metal atom. For example, CuC2N2 is a chelate where a ring of atoms is formed including the central metal atom, copper.
by Michelle Shin 4B
Sun Dec 01, 2019 5:54 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Acids Vs. Bases
Replies: 11
Views: 149

Re: Acids Vs. Bases

Acids donate H+ ions(proton) and bases accept H+. Bases also produce OH- while acids produce H+. If you compare the hydrogens before and after a reaction, you can tell if the substance is an acid (decrease H+ =acid) or a base (increase=base).
by Michelle Shin 4B
Sun Nov 24, 2019 9:20 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination Sphere
Replies: 5
Views: 58

Re: Coordination Sphere

Ligands directly attached to the central ion make up the first coordination sphere, and the second coordination sphere consists of atoms/molecules attached to those in the first coordination sphere. Everything inside the brackets will be inside the coordination sphere.
by Michelle Shin 4B
Sun Nov 24, 2019 9:13 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Transition Metals
Replies: 7
Views: 74

Transition Metals

Do all transition metals form coordination compounds or just the ones mentioned in lecture?
by Michelle Shin 4B
Sun Nov 24, 2019 9:06 pm
Forum: Ionic & Covalent Bonds
Topic: ligands
Replies: 5
Views: 170

Re: ligands

Ligands are electron pair donors that have at least one lone pair.
by Michelle Shin 4B
Sun Nov 24, 2019 9:05 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand
Replies: 10
Views: 82

Re: Ligand

A ligand is also an electron pair donor, so it must have at least one or more lone pairs.
by Michelle Shin 4B
Sun Nov 24, 2019 9:02 pm
Forum: Sigma & Pi Bonds
Topic: sigma and pi bonds
Replies: 19
Views: 336

Re: sigma and pi bonds

Yes, and there are also two pi bonds and one sigma bond in a triple bond.
by Michelle Shin 4B
Sun Nov 17, 2019 8:50 pm
Forum: Lewis Structures
Topic: Why can Xenon break the octet rule?
Replies: 8
Views: 153

Re: Why can Xenon break the octet rule?

In Xenon Tetrafluoride (XeF4), it breaks the octet rule to achieve a formal charge of zero in addition to it being higher than n=3.
by Michelle Shin 4B
Sun Nov 17, 2019 8:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 3
Views: 37

Re: Bond Angles

Linear: 180
Trigonal Planar: 120
Tetrahedral: 109.5
Trigonal Pyramidal: trigonal bond angles are 120 while the axial bond angles are 90 and 180
Octahedral: 90 and 180

If there are lone pairs, they repel so the bond angle is smaller.
Ex: NH3 has bond angles of 107 instead of 109.5
by Michelle Shin 4B
Sun Nov 17, 2019 8:34 pm
Forum: Sigma & Pi Bonds
Topic: sigma and pi bonds
Replies: 4
Views: 33

Re: sigma and pi bonds

Sigma bonds are also generally stronger than pi bonds and sigma can exist independently.
by Michelle Shin 4B
Sun Nov 17, 2019 8:24 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angle
Replies: 3
Views: 22

Re: Bond angle

I believe we only need to know that it is less than a specific bond angle because it can differ for molecules such as H2O (104.5) and NH3 (107).
by Michelle Shin 4B
Sun Nov 17, 2019 8:20 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 3
Views: 29

Re: Bond Angles

The repulsion caused by the lone pairs results in a smaller bond angle. For example, NH3 is trigonal pyramidal because is has one lone pair and has a bond angle of 107 instead of 109.
by Michelle Shin 4B
Sun Nov 10, 2019 6:28 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: Boiling point
Replies: 5
Views: 52

Re: Boiling point

Stronger bonds have higher boiling points because it takes more energy to boil. Ionic and Hydrogen bonds have higher boiling points while covalent bonds usually have lower boiling points.
by Michelle Shin 4B
Sun Nov 10, 2019 5:27 pm
Forum: Sigma & Pi Bonds
Topic: sigma bonds
Replies: 3
Views: 49

Re: sigma bonds

A single bond has one sigma bond. In a double bond, there is one sigma and one pi bond. In a triple bond, there is one sigma bond and 2 pi bonds.
by Michelle Shin 4B
Sun Nov 10, 2019 5:25 pm
Forum: Dipole Moments
Topic: Hydrogen bonding base pairs
Replies: 4
Views: 36

Hydrogen bonding base pairs

What is the difference between the AT and GC base pairs in the hydrogen bonding example used in lecture?
by Michelle Shin 4B
Sun Nov 10, 2019 5:16 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent Character
Replies: 3
Views: 34

Re: Covalent Character

Increasing covalent character is when the electrons get further from the nucleus and it becomes easier to share electrons with other atoms. As the polarizability of anion increase and the polarizing power of a cation increases, the covalent character also increases.
by Michelle Shin 4B
Sun Nov 10, 2019 5:07 pm
Forum: Electronegativity
Topic: Iodine
Replies: 6
Views: 60

Re: Iodine

Because I2 is a bigger molecule, it has stronger London dispersion forces.
by Michelle Shin 4B
Sat Nov 02, 2019 5:18 pm
Forum: Lewis Structures
Topic: Double Bonds vs. Lone Pairs
Replies: 2
Views: 26

Re: Double Bonds vs. Lone Pairs

After counting the number of valence electrons for each atom, use single bonds and put lone pairs on the atoms starting from the outside. Consider formal charge when drawing lewis structures to determine whether or not to use double bonds and make sure the total number of electrons matches that of t...
by Michelle Shin 4B
Sat Nov 02, 2019 5:07 pm
Forum: Formal Charge and Oxidation Numbers
Topic: CNS- formal charge
Replies: 2
Views: 42

CNS- formal charge

In the lecture, we went over how the best version of CNS- is when the formal charge of -1 is on the S. Why is the formal charge of -1 on sulfur and not on nitrogen?
by Michelle Shin 4B
Sat Nov 02, 2019 5:03 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Minimize formal charge of whole molecule?
Replies: 7
Views: 70

Re: Minimize formal charge of whole molecule?

Having the formal charge for each individual atom equal zero is usually best as well as minimizing the total formal charge.
by Michelle Shin 4B
Sat Nov 02, 2019 4:59 pm
Forum: Properties of Electrons
Topic: Schrodinger Equation
Replies: 2
Views: 148

Re: Schrodinger Equation

Schrodinger's wave function equation uses the concept that an electron with wave-like properties and indeterminacy in momentum and position can be described by a wave function. This equation can also be solved for 1 electron atoms.
by Michelle Shin 4B
Sat Nov 02, 2019 3:46 pm
Forum: Ionic & Covalent Bonds
Topic: Dissociation energy
Replies: 3
Views: 27

Re: Dissociation energy

The dissociation energy also increases as the difference between the electronegativity of atoms increases.
by Michelle Shin 4B
Sat Oct 26, 2019 3:20 pm
Forum: Lewis Structures
Topic: 2B.1
Replies: 2
Views: 39

Re: 2B.1

The best structure would be with the double bond between oxygen and nitrogen and a single bond between nitrogen and fluorine since this would result in all the formal charges being zero (the best structure).
by Michelle Shin 4B
Sat Oct 26, 2019 3:17 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: #1E17 help
Replies: 1
Views: 27

Re: #1E17 help

An electron will be removed from the 4s orbital because the 4s orbital has a lower energy than 3d. 4s has higher energy when when the 4s state is occupied AND electrons enter the 3d state.
by Michelle Shin 4B
Sat Oct 26, 2019 3:04 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge Formula
Replies: 5
Views: 57

Formal Charge Formula

What are the shared electrons (S) for the formula FC= V -(L + (S/2)) and how do you count them?
by Michelle Shin 4B
Sat Oct 26, 2019 3:01 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Expanded Valence Shells
Replies: 5
Views: 61

Re: Expanded Valence Shells

The elements P, S, and Cl can accommodate more than 8 valence electrons since atoms in period 3 or higher have d-orbitals that can accommodate more electrons.
by Michelle Shin 4B
Sat Oct 26, 2019 2:58 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Checking bonding
Replies: 3
Views: 58

Re: Checking bonding

Comparing the formal charges of atoms in Lewis structures helps you find which is the more stable structure, but I'm not sure if this is the only method to see which is the best structure.
by Michelle Shin 4B
Sun Oct 20, 2019 6:16 pm
Forum: Properties of Light
Topic: Question 1A.3
Replies: 3
Views: 56

Re: Question 1A.3

Because the waves broaden and the extent of change decreases when the frequency decreases, c is the correct answer.
by Michelle Shin 4B
Sun Oct 20, 2019 6:11 pm
Forum: Quantum Numbers and The H-Atom
Topic: Magnetic Quantum Number ml
Replies: 5
Views: 39

Re: Magnetic Quantum Number ml

The magnetic quantum number labels different orbitals of a subshell (orientation) that an electron occupies.
by Michelle Shin 4B
Sun Oct 20, 2019 6:08 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Configuration of 3d and 4s orbitals
Replies: 1
Views: 20

Configuration of 3d and 4s orbitals

Why is the electron configuration of scandium [Ar] 3d^1 4s^2 and not [Ar] 4s^2 3d^1 ?
by Michelle Shin 4B
Sun Oct 20, 2019 6:02 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration
Replies: 5
Views: 61

Re: Electron Configuration

You start using the d orbital after the 4s state since the 4s state is slightly lower energy than 3d.
by Michelle Shin 4B
Sun Oct 20, 2019 5:56 pm
Forum: DeBroglie Equation
Topic: Wave properties module
Replies: 2
Views: 55

Re: Wave properties module

Electric cars do not have wavelike properties because the properties are negligible, and yes, you should convert it to m/s.
by Michelle Shin 4B
Sun Oct 13, 2019 2:02 pm
Forum: Properties of Light
Topic: Speed of Light
Replies: 3
Views: 19

Re: Speed of Light

The wavelength changes, but the frequency remains constant in order to conserve energy.
by Michelle Shin 4B
Sun Oct 13, 2019 1:58 pm
Forum: Properties of Light
Topic: EM waves
Replies: 3
Views: 28

Re: EM waves

Electromagnetic waves are the result of a disturbance in the electromagnetic field.
by Michelle Shin 4B
Sun Oct 13, 2019 1:30 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Atomic Spectra for H
Replies: 5
Views: 54

Re: Atomic Spectra for H

The equation is En=-hR/n^2. This applies only to atoms with one electron (hydrogen) because if there were more, then they would repel each other.
by Michelle Shin 4B
Sun Oct 13, 2019 12:22 pm
Forum: DeBroglie Equation
Topic: De Broglie Equation Clarification
Replies: 4
Views: 58

Re: De Broglie Equation Clarification

The wavelike properties are the diffraction patterns: constructive (waves in phase) and destructive interference (waves out of phase).
by Michelle Shin 4B
Sun Oct 13, 2019 12:00 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: En=-hR/n^2
Replies: 3
Views: 65

Re: En=-hR/n^2

Yes I believe this is used to calculate the energy levels in hydrogen and will only work for atoms with a single electron.
by Michelle Shin 4B
Thu Oct 03, 2019 11:14 am
Forum: SI Units, Unit Conversions
Topic: Dimensional Analysis Question
Replies: 6
Views: 58

Re: Dimensional Analysis Question

Yes you're right about using various ratios to get to the end answer. For example, when you are trying to convert 100 meters per sec to meters per minute, you would begin with the given 100m/s and multiply by the ratio 60sec/1 min since you are trying to solve for meters per minute. The seconds woul...
by Michelle Shin 4B
Thu Oct 03, 2019 11:05 am
Forum: Significant Figures
Topic: Determining Sig Fig's
Replies: 5
Views: 77

Re: Determining Sig Fig's

Also make sure to only round for sig figs at the end of your calculations to ensure that you get the most accurate answer possible.
by Michelle Shin 4B
Wed Oct 02, 2019 10:24 pm
Forum: Significant Figures
Topic: Question About Significant Figures and Rounding
Replies: 22
Views: 808

Re: Question About Significant Figures and Rounding

I think for the molar masses given in the periodic table you should round to two places after the decimal, which I believe is generally the rule of thumb.
by Michelle Shin 4B
Wed Oct 02, 2019 10:13 pm
Forum: Balancing Chemical Reactions
Topic: Fundamental H5 D
Replies: 3
Views: 45

Fundamental H5 D

To balance Fe2P (s) + S(s) -> P4S10 (s) + FeS(s), how do you know which element to start balancing first?
by Michelle Shin 4B
Wed Oct 02, 2019 8:41 pm
Forum: SI Units, Unit Conversions
Topic: Sig figs
Replies: 18
Views: 292

Re: Sig figs

For sig figs make sure to use the smallest value of sig figs in the given (ex. 4.00 is 3 sig figs) and also use at the end of calculations.

Go to advanced search