## Search found 59 matches

Thu Jan 14, 2021 10:31 pm
Forum: Ideal Gases
Topic: Question 4 Sapling [ENDORSED]
Replies: 8
Views: 118

### Question 4 Sapling[ENDORSED]

I am having quite a bit of trouble on this problem. I understand that I may have to set up an equilibrium constant expression and subsequent quadratic equation and solve for x, plug x back in to the equilibrium and add because the total pressure is the sum of the partial pressures but I am still stu...
Sun Jan 10, 2021 9:18 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Pressure and Volume
Replies: 16
Views: 38

### Re: Pressure and Volume

From my understanding they are inversely proportional. In other words as one increases the other decreases.
Sun Jan 10, 2021 9:09 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs P
Replies: 6
Views: 32

### Re: K vs P

Kc vs Kp Fro my understanding they both have to do with the equilibrium constant it is just that Kp is when you are dealing with pressure and gas and Kc is everything that does not fit into that category.
Sun Jan 10, 2021 9:03 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K relationship
Replies: 12
Views: 42

### Re: Q and K relationship

From my understanding its best to imagine the relationship like this: <------|------------|-------------|-----------> -------Q ---------->K<------------Q If Q is less than K the reaction will shift to the right If Q is greater than K the reaction will shift left If Q=K the reaction is at equilibrium...
Sun Jan 10, 2021 8:59 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Removing product
Replies: 5
Views: 16

### Re: Removing product

When you remove the product you disturb the equilibrium and to counteract that the reaction will produce more products to "stabilize" the reaction again. I put reaction in quotes because a reaction is never truly stable the products and reactants are moving back and forth but at equal rate...
Tue Jan 05, 2021 2:03 pm
Forum: Ideal Gases
Topic: Units of Temperature
Replies: 82
Views: 286

### Re: Units of Temperature

From what I have seen usually questions will provide us with the temperature in Celsius and we are expected to covert it to Kelvin.
Sat Dec 12, 2020 10:34 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6B.1 Dilution and pH
Replies: 3
Views: 27

### Re: 6B.1 Dilution and pH

The way that I approached the question was to assign values for the concentrations of HCl in solution, as long as the values met the criteria. I began with 1.0 M HCl in a 1L solution, which would yield 1.0 mol of HCl. Since the dilution reduced the HCl to 12% of its initial value, there would be 1....
Sat Dec 12, 2020 12:55 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6B.1 Dilution and pH
Replies: 3
Views: 27

### 6B.1 Dilution and pH

The question asks: The molar concentration of HCl in hydrochloric acid is reduced to 12% of its initial value by dilution. What is the difference in the pH values of the two solutions? Can someone walk through how they would go about solving this question? What information do I need to know before I...
Sat Dec 12, 2020 12:48 am
Forum: Bronsted Acids & Bases
Topic: Arrhenius acids and bases
Replies: 2
Views: 15

### Re: Arrhenius acids and bases

I don't think we have to know Arrhenius acids and bases in-depth, especially because Dr. Lavelle didn't go over them. I think I remember from one of the UA review sessions that your definition would be enough in terms of just knowing what they are for the final. However, I think we don't really nee...
Sat Dec 12, 2020 12:47 am
Forum: Bronsted Acids & Bases
Topic: experiments to know
Replies: 1
Views: 28

### Re: experiments to know

Although these are not experiments I would add that you might want to be familiar with the ideas behind the DeBroglie equation, Heisenberg’s indeterminacy equation, and Bronsted and Lewis acids and bases. As far as experiments I believe you covered them all!
Sat Dec 12, 2020 12:43 am
Forum: Bronsted Acids & Bases
Topic: Arrhenius acids and bases
Replies: 2
Views: 15

### Arrhenius acids and bases

In addition to Lewis and Bronsted acids and bases do we have to study in depth about Arrhenius acids and bases? If so, is it enough to know that Arrhenius acids produce hydrogen ions and Arrhenius bases contain hydroxide ions?
Thu Dec 10, 2020 10:07 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: pKa
Replies: 3
Views: 36

### Re: pKa

I would also remember henderson hasselbalch equation and be able to use it to solve for Ka [A-] and [HA].
Thu Dec 10, 2020 10:05 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strong Acid Question (How to Derive)
Replies: 3
Views: 26

### Re: Strong Acid Question (How to Derive)

Honestly I think its best to memorize them and the trends associated with them so you can identify them quickly on the exam. Acids usually start with H and some end in COOH. Strong bases that we are interested in contain OH and weak bases of our interest typically contain N.
Thu Dec 10, 2020 9:18 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: pKa greater than pH
Replies: 3
Views: 32

### pKa greater than pH

Someone wrote that when pKa is less than pH the acid will give off proton(s) and become negatively charged. So my question is does this mean that when pKa is greater than pH the acid gains protons and becomes positively charged? Or does not reaction happen at all because we are only looking at wheth...
Tue Dec 08, 2020 10:00 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 5
Views: 54

### Re: Bond Angles

From my understanding, the angles mark the distance between one oxygen, back to the sodium molecule and back out to the next oxygen. I believe that the reason the distance does not add up to 360 degrees is because the oxygen molecules themselves occupy space within the "circle" of the comp...
Wed Dec 02, 2020 5:34 pm
Forum: Bronsted Acids & Bases
Topic: Strength of Bronsted bases
Replies: 1
Views: 18

### Strength of Bronsted bases

Because NH3 only has 1 lone pair of electrons it is considered a weak base so then would HBr be considered a strong base because it has 3 lone pairs? This topic is a little cloudy for me still...
Tue Dec 01, 2020 9:11 pm
Forum: Lewis Acids & Bases
Topic: Lewis Acids and Bases
Replies: 3
Views: 42

### Re: Lewis Acids and Bases

To add to what Akshata mentioned, I think it is also important to note that when a Brønsted acid dissociates, it increases the concentration of H+ ions in the solution; conversely, Brønsted bases dissociate by taking a proton Fromm the solvent (water) to generate [OH-]. It is also important to under...
Mon Nov 30, 2020 9:29 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Textbook 2F 15
Replies: 2
Views: 30

### Re: Textbook 2F 15

I believe the bond angle would increase. Based on the fact that in the sp hybrid, 1 of the 2 orbitals are s. Where as in the sp2 hybrid, 1 out of the 3 orbitals are s. Looking at them as fractions helps me with this concept.
Mon Nov 30, 2020 8:59 pm
Forum: Naming
Topic: Tips for Naming Coordination Compounds
Replies: 6
Views: 36

### Tips for Naming Coordination Compounds

I understand that when naming a coordination compound the cation comes first and then the ligands in the complex ion are next in alphabetical order, next is the metal atom or ion before the ligands in the chemical formula but I am still a tad bit confused. Does anyone have any tips that they utilize...
Mon Nov 30, 2020 8:28 pm
Forum: Biological Examples
Topic: Biological Functions of Transition Metals
Replies: 5
Views: 62

### Re: Biological Functions of Transition Metals

Just remember when looking at the first row that they each have unique biological functions and you should be fine.
Mon Nov 30, 2020 8:25 pm
Forum: Biological Examples
Topic: Biological function of sigma and pi bonds
Replies: 4
Views: 48

### Biological function of sigma and pi bonds

Is is sufficient enough to know that if an atom has one bond it is a sigma bond, and double and triple bonds contain sigma and pi bonds with double bonds having one each and triple bonds having one sigma and 2 pi bonds? I feel like that could be enough info but I just want to be sure I understand it...
Wed Nov 25, 2020 8:52 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate Compounds
Replies: 5
Views: 55

### Re: Coordinate Compounds

From my understanding, any molecule can be a coordination compound as long as it poses one or more metal centers that is bound to ligands or anything that donates electrons to the metal.
Tue Nov 24, 2020 10:18 pm
Forum: Student Social/Study Group
Replies: 86
Views: 859

### Re: Big Sad: Midterm 2

I understand exactly how you feel, the most troubling part is that I really practiced and studied for it too. Hopefully we all hit it out of the park on the final!
Tue Nov 24, 2020 10:13 pm
Forum: Dipole Moments
Topic: 2E #29
Replies: 7
Views: 32

### Re: 2E #29

From my understanding, dipole moments tell you how polar a bond is. So first find the most polar bond, or bond with the greatest difference in electronegativity.
Tue Nov 24, 2020 10:06 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR Simulation
Replies: 2
Views: 29

### Re: VSEPR Simulation

Thank you so much you are too kind!
Tue Nov 24, 2020 10:04 pm
Forum: Determining Molecular Shape (VSEPR)
Replies: 6
Views: 74

### Re: Important aspects of Radicals

Another thing that is important to at-least be familiar with is that the formation of radicals sometimes involves the breaking of covalent bonds, and that process can requires significant amounts of energy.
Tue Nov 24, 2020 9:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Ways to remember VSEPR
Replies: 6
Views: 87

### Re: Ways to remember VSEPR

Honestly, what helps me is watching videos on the topic and writing. To memorize things I write using pencil and paper over and over again until it becomes muscle memory. Then, when its time for the exam you will have practiced it so many times you will be able to recreate the table in real time to ...
Tue Nov 24, 2020 9:44 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Expanded Octets
Replies: 9
Views: 85

### Re: Expanded Octets

Yes elements there can have an expanded octet. As long as the element meets the criteria of having d-orbitals and are located in the third period it can happen.
Tue Nov 24, 2020 9:38 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/vapor pressure
Replies: 5
Views: 64

### Re: Boiling Point/vapor pressure

From my understanding, a high vapor pressure leads to a low boiling point.
Tue Nov 24, 2020 9:36 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: H-bonding
Replies: 5
Views: 56

### Re: H-bonding

You are correct in assuming that!
Tue Nov 24, 2020 9:30 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: High Vapor Pressure, Solubility, Boiling Point
Replies: 5
Views: 54

### Re: High Vapor Pressure, Solubility, Boiling Point

MCalcagnie_ 2H wrote:Clearly I didn't fully understand this concept haha thanks for clarifying everyone!

Literally! This forum helps me so much!
Tue Nov 24, 2020 9:27 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 bonds and dipole-dipole
Replies: 8
Views: 92

### Re: Hydrogen bonds and dipole-dipole

Yes because the two are almost one in the same, a H bond is a type of dipole-dipole interaction!
Tue Nov 24, 2020 9:23 pm
Forum: Trends in The Periodic Table
Topic: Textbook Question Focus 1.13
Replies: 2
Views: 17

### Re: Textbook Question Focus 1.13

From my understanding, O has lower ionization enthalpy than N because N has a half-filled electron configuration. The lower ionization enthalpy of O is less than F because of the higher electronegativity and high effective nuclear charge of F. Hope this helps!
Tue Nov 24, 2020 9:17 pm
Forum: Bond Lengths & Energies
Topic: textbook 2.27
Replies: 2
Views: 42

### Re: textbook 2.27

I know that to find bond length we have to refer to the trends of ionic/atomic radii. I would just compare each atom and as long as things align with the rules of the trend you should be fine.
Tue Nov 24, 2020 9:15 pm
Forum: Bond Lengths & Energies
Topic: Bond Length vs Size of Molecule
Replies: 14
Views: 130

### Re: Bond Length vs Size of Molecule

You are right larger atoms do have weaker bonds, it's just that boiling also weakens bonds. Sometimes the two relate to each other sometimes they do not it depends from situation to situation.
Tue Nov 24, 2020 9:13 pm
Forum: Bond Lengths & Energies
Topic: Outline 3 - Covalent Bond Dissociation Energy
Replies: 3
Views: 69

### Re: Outline 3 - Covalent Bond Dissociation Energy

You almost have it! Like it has already been said, covalent bond multiplicity has to do with bond order, atomic radius is the distance between atoms, and unpaired e- refers to the lone pairs of neighboring atoms. More unpaired electrons means that it is more likely that you are dealing with a weaker...
Thu Nov 19, 2020 11:48 am
Forum: Electronegativity
Replies: 8
Views: 42

I understand where we apply the principles of electronegativity but how does the trend of atomic radius relate to physical effects on the elements that we can use to study them?
Sat Nov 14, 2020 4:14 pm
Forum: Electronegativity
Topic: Textbook 2D problem #7
Replies: 3
Views: 24

### Re: Textbook 2D problem #7

I think Ba is correct because Ba has a lower electronegativity and therefore a lower covalent character so by association Ba is more soluble in water than Mg.
Sat Nov 14, 2020 3:58 pm
Forum: Electronegativity
Topic: London Dispersion Forces
Replies: 9
Views: 87

### Re: London Dispersion Forces

The biggest thing that helps me is looking at polarity. First, I knew that choice E was correct because there is no electronegativity difference between the Br atoms (only can have London dispersion forces). Next, I looked for hydrocarbons (choice A). They are not polar, and can only have London di...
Sat Nov 14, 2020 3:50 pm
Forum: Ionic & Covalent Bonds
Topic: Electronegativity
Replies: 18
Views: 104

### Re: Electronegativity

I noticed that too and honestly I suggest you use the trends on the periodic table to guide you those can point you in the general direction for the types of problems we are doing right now. There are other tables provided in the textbook but I doubt we will be able to use those on an exam. If anyon...
Sun Nov 08, 2020 3:43 pm
Forum: Ionic & Covalent Bonds
Topic: Salts and molecules
Replies: 4
Views: 45

### Re: Salts and molecules

Hello
Yes, because salts are help together by ionic bonds and contain cations and anions and molecules are held together by covalent bonds.
Thu Nov 05, 2020 8:29 pm
Forum: SI Units, Unit Conversions
Topic: Converting equations
Replies: 14
Views: 124

### Re: Converting equations

I suggest being extremely through, writing out every step with its corresponding units, maybe even a sentence on the side describing what you did during that step before moving on.
Thu Nov 05, 2020 8:22 pm
Forum: Einstein Equation
Topic: E=hv vs E=hf
Replies: 15
Views: 120

### Re: E=hv vs E=hf

Use whatever one you prefer, they are interchangeable!
Thu Nov 05, 2020 12:51 pm
Forum: Electronegativity
Topic: Periodic Table Trend
Replies: 37
Views: 387

### Re: Periodic Table Trend

Increases across a period and increases as you move up/decreases down a group.
Thu Nov 05, 2020 12:49 pm
Forum: Octet Exceptions
Topic: Octet Rule
Replies: 3
Views: 42

### Re: Octet Rule

I know that hydrogen, beryllium, and boron are electron deficient and because of that they have too few electrons to form an octet. There may be more exceptions though.
Thu Nov 05, 2020 12:41 pm
Forum: Ionic & Covalent Bonds
Topic: Electron Affinity
Replies: 5
Views: 43

### Re: Electron Affinity

Sun Nov 01, 2020 11:03 am
Forum: Properties of Light
Topic: Which model of light is atomic spectroscopy?
Replies: 8
Views: 96

### Re: Which model of light is atomic spectroscopy?

The particle model!
Sun Nov 01, 2020 11:03 am
Forum: Properties of Light
Topic: Midterm
Replies: 6
Views: 70

### Re: Midterm

Partial points will be afforded but from what I have heard so far there will not be a curve on this exam or in the class in general.
Sun Nov 01, 2020 10:53 am
Forum: Student Social/Study Group
Topic: Tips for Staying Focused
Replies: 52
Views: 522

### Re: Tips for Staying Focused

I suggest studying in intervals of 25 minutes and taking a 5 minute break before returning. This prevents burnout and gives you time to recenter yourself!
Sun Nov 01, 2020 10:51 am
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 226
Views: 35969

### Re: Final Jitters

Recently I found that having cup of tea or water by my side helps me. I suggest tea because the smell might calm you even if you do not stop for a drink.
Sun Nov 01, 2020 10:45 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orbital vs. Subshell
Replies: 13
Views: 93

### Re: Orbital vs. Subshell

The best way I can explain it is that sub-shells are a part of shells and each sub-shell contains at least one orbital and orbitals can hold 2 electrons (maximum).
Sun Nov 01, 2020 10:36 am
Forum: Balancing Chemical Reactions
Topic: Periodic Table
Replies: 50
Views: 482

### Re: Periodic Table

No not at all just understand how to read it and you will be just fine!
Sun Nov 01, 2020 10:34 am
Forum: DeBroglie Equation
Topic: When to Use De Broglie
Replies: 16
Views: 127

### Re: When to Use De Broglie

If you are dealing with mass or velocity this formula is the best.
Sun Nov 01, 2020 10:32 am
Forum: Photoelectric Effect
Topic: Work function or incoming light
Replies: 6
Views: 51

### Re: Work function or incoming light

In this case they would be asking you to find the work function/threshold energy.
Sun Nov 01, 2020 10:30 am
Forum: Photoelectric Effect
Topic: Photoelectric Effect
Replies: 13
Views: 119

### Re: Photoelectric Effect

No, unfortunately there is not any fun chemistry there it just passes through the material.
Sun Nov 01, 2020 10:29 am
Forum: Photoelectric Effect
Topic: Sapling using de broglie's
Replies: 7
Views: 78

### Re: Sapling using de broglie's

You may need to convert grams to kilograms, good luck!
Sun Nov 01, 2020 10:27 am
Forum: Significant Figures
Topic: All students read this sig fig post [ENDORSED]
Replies: 133
Views: 17952

### Re: All students read this sig fig post[ENDORSED]

Jordanmjones13 wrote:Do you know if the problems will specifically tell us how many significant figures to use?

No, and because this is a useful tool for chemistry in general it is best that we learn the rules although they are tasking at times. Good luck!
Sun Nov 01, 2020 10:23 am
Forum: Einstein Equation
Topic: E=hv vs. E=1/2mv^2
Replies: 6
Views: 72

### Re: E=hv vs. E=1/2mv^2

You are suppose to use E=hv with protons because they do not have mass thus the m is missing from the equation. While for E=1/2mv^2 is used for electrons or anything else that has mass and most of the time in the problem they either give you the velocity or the mass which is a huge giveaway to whic...
Sun Nov 01, 2020 10:21 am
Forum: Properties of Light
Topic: Is c always the speed of light?
Replies: 88
Views: 457

### Re: Is c always the speed of light?

For our purposes, yes. Speed will always be C or 3*10^8 :).