## Search found 39 matches

Mon Jan 28, 2019 10:06 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: eq constant
Replies: 1
Views: 138

### eq constant

Can we find equilibrium composition for a set of reactions using Gibbs minimization method?
Mon Jan 28, 2019 10:02 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: eq constants for acids
Replies: 4
Views: 241

### eq constants for acids

why do strong acids not have equilibrium constants? is it because the acid dissociates completely?
Mon Jan 28, 2019 10:00 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Salts
Replies: 1
Views: 117

### Salts

do salts affect the pH of a solution? how can we identify them as salts?
Tue Jan 15, 2019 5:21 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Solids and liquids in equilibrium constants?
Replies: 2
Views: 92

### Re: Solids and liquids in equilibrium constants?

They're not included because they do not affect the reactant amount at equilibrium in the reaction, so they are disregarded and kept at 1.
Tue Jan 15, 2019 5:16 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Temperature
Replies: 3
Views: 130

### Re: Temperature

Unless it says otherwise, we should be using Kelvin, and converting other units into Kelvin
Tue Jan 15, 2019 4:36 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Exothermic vs. Endothermic Reaction
Replies: 9
Views: 1149

### Re: Exothermic vs. Endothermic Reaction

I don't think you can tell whether a reaction is exothermic or endothermic by the equation alone. You have to either measure the heating to cooling or know enough about similar types of reactions.
Sun Dec 09, 2018 8:55 pm
Forum: Resonance Structures
Topic: Resonance of CH3COOH
Replies: 1
Views: 1427

### Re: Resonance of CH3COOH

yes
Sun Dec 09, 2018 8:50 pm
Forum: Administrative Questions and Class Announcements
Replies: 7
Views: 489

I know that we get our physical tests back in the second week of winter quarter
Sun Dec 09, 2018 8:49 pm
Forum: Lewis Acids & Bases
Topic: Ions as Bases
Replies: 1
Views: 222

### Re: Ions as Bases

yes
Sun Dec 09, 2018 8:48 pm
Forum: Bronsted Acids & Bases
Topic: Oxoacids
Replies: 1
Views: 388

### Re: Oxoacids

As electron density of the O—H bond decreases, the bond becomes more polar. As the O—H becomes more polar, the oxoacid more readily dissolves in water. Therefore, acid strength increases as the number of oxygen attached to the central atom increases.
Sat Dec 08, 2018 11:27 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Polarizability and Polarizing Power
Replies: 3
Views: 235

### Re: Polarizability and Polarizing Power

The polarizability of an atom increases the bigger the anion it is. The polarizing power of an atom increases the smaller the cation it is.
Sat Dec 08, 2018 11:16 am
Forum: Naming
Topic: using prefix "mono"
Replies: 2
Views: 149

### Re: using prefix "mono"

I'm pretty sure we don't use a prefix to identify one molecule. I'm pretty sure the first prefix we use is bis-.
Sat Dec 08, 2018 11:14 am
Forum: Biological Examples
Topic: Ligands
Replies: 7
Views: 501

### Re: Ligands

The ligand is also the same as the Lewis base in any given molecule, and the central atom is almost always the Lewis acid
Sat Dec 08, 2018 11:11 am
Forum: Biological Examples
Topic: VSEPR model
Replies: 2
Views: 2309

### Re: VSEPR model

VSEPR theory states that the electron pairs in the valence shell of an atom arrange themselves in such a way that repulsions among them are minimized and this arrangement of the electron pairs determines the shape of a particular molecule. Hybridization is the intermixing of a particular number of a...
Sat Dec 08, 2018 11:08 am
Forum: Bronsted Acids & Bases
Topic: H vs OH
Replies: 3
Views: 235

### H vs OH

Are A-H bonds stronger than AO-H bonds?
Sat Dec 08, 2018 11:06 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8548
Views: 1474836

### Re: Post All Chemistry Jokes Here

Q: Why shouldn't you believe anything alcohol says?
A: 'Cause alkyl ha-lide
Sat Dec 08, 2018 11:05 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8548
Views: 1474836

### Re: Post All Chemistry Jokes Here

Q: What did the pregnant scientist say at the end of her electrolysis experiment?
A: "My water broke."
Tue Dec 04, 2018 2:22 pm
Forum: Conjugate Acids & Bases
Topic: Inductive Effect
Replies: 5
Views: 272

### Inductive Effect

What is inductive effect? And how does it relate to electronegativity?
Sun Nov 25, 2018 11:41 am
Forum: Dipole Moments
Topic: What are dipole moments used for?
Replies: 3
Views: 177

### Re: What are dipole moments used for?

dipole moments refer to the distribution of electrons between two bonded atoms, normally between a polar and nonpolar bond. molecules with a net dipole moment are polar molecules. if the net dipole moment is zero or very small, the bond and molecule are considered to be nonpolar. atoms that have sim...
Sun Nov 25, 2018 11:39 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8548
Views: 1474836

### Re: Post All Chemistry Jokes Here

Q: did you know proton's have mass?
A: i didn't even know they were catholic...
Sun Nov 25, 2018 11:36 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8548
Views: 1474836

### Re: Post All Chemistry Jokes Here

I would tell another chemistry joke...
... but all the good ones Argon
Mon Nov 19, 2018 6:54 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Different-looking N — H bonds in the Lewis structure for Ammonia (NH3)
Replies: 3
Views: 221

### Re: Different-looking N — H bonds in the Lewis structure for Ammonia (NH3)

The different bonds all essentially represent the same thing all they show is the 3D model of the molecule and how the atoms are all in different planes.
Mon Nov 19, 2018 6:53 pm
Forum: Bond Lengths & Energies
Topic: VSEPR
Replies: 6
Views: 890

### Re: VSEPR

You would need to first draw the lewis structure for the compound, and then see how many bonds the molecule has and how many lone pairs the central atom as. Depending on that final number, you can determine the shape and the corresponding bond angle.
Mon Nov 19, 2018 6:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Chem 14B
Replies: 2
Views: 190

### Re: Chem 14B

math is an enforced co requisite so you would have to take a 3B, 31B, or LS30B the quarter before you take 14B or at the same time you take 14B
Sun Nov 04, 2018 9:01 pm
Forum: Octet Exceptions
Replies: 16
Views: 976

How would you define a radical?
Sun Nov 04, 2018 8:59 pm
Forum: Lewis Structures
Topic: 7th edition 2B.7
Replies: 2
Views: 110

### Re: 7th edition 2B.7

From counting up all the lone pairs and bonds, you can calculate the total number of valence electrons for the compound. In this case, there are 32 VE. The diagram shows you how many Cl and O atoms are in the compound, so using that you can calculate the number of VE that come from those two atoms. ...
Sun Nov 04, 2018 8:42 pm
Forum: Administrative Questions and Class Announcements
Topic: Monday review sessions
Replies: 2
Views: 189

### Re: Monday review sessions

I heard they're all going to be the same so it won't necessarily matter which lecture you decide to go to. You could always ask friends in other lectures for their notes as well if it's different!
Mon Oct 29, 2018 8:22 pm
Forum: Lewis Structures
Topic: Number of Electrons
Replies: 2
Views: 52

### Re: Number of Electrons

The number of protons is the same as the number of electrons if the atom is neutral and not charged. The number of valence electrons is based off of the group number the element is in.
Mon Oct 29, 2018 8:20 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Energy Levels
Replies: 2
Views: 207

### Re: Energy Levels

Electrons gain energy and become less stable as they move away from the nucleus. As it quantum number increases, the electron gains/absorbs energy from surroundings, which is also known as absorption of energy.
Mon Oct 29, 2018 1:43 pm
Forum: Octet Exceptions
Topic: Sulfate Ion structure
Replies: 2
Views: 132

### Re: Sulfate Ion structure

Sulfur is one of the exceptions to the octet rule. Sulfur is able to hold more than eight electrons due to its bonding. It's also a third period element which means the d sub level exists, and it has five d orbitals. Therefore, the additional d orbitals can accommodate for more electrons.
Sun Oct 21, 2018 6:29 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Shape of Orbitals
Replies: 3
Views: 172

### Re: Shape of Orbitals

lavelle mentioned that we will not be asked to draw the orbital shapes on our tests
Sun Oct 21, 2018 1:17 pm
Forum: Significant Figures
Topic: Sig figs and percentages
Replies: 3
Views: 727

### Re: Sig figs and percentages

No, percentages do not count at sig figs.
Sun Oct 21, 2018 1:12 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Atomic Spectroscopy vs Molecular Spectroscopy
Replies: 1
Views: 227

### Re: Atomic Spectroscopy vs Molecular Spectroscopy

The main difference between the two is their energy levels. Molecular spectroscopy looks at the interactions between electrons in the outer valence shell and electromagnetic waves, which change based off of the structure and composition of the molecule. Atomic spectroscopy is only concerned with the...
Mon Oct 15, 2018 2:34 pm
Forum: Properties of Light
Topic: 7th Edition HW 1B.27
Replies: 1
Views: 49

### Re: 7th Edition HW 1B.27

to solve for minimum uncertainty you would use the uncertainty principle which is x=1/2(h/mv). the final answer should be x = 1.3 x 10^-36 m
Mon Oct 15, 2018 2:32 pm
Forum: Quantum Numbers and The H-Atom
Topic: 7th Edition HW 1D.21
Replies: 3
Views: 174

### Re: 7th Edition HW 1D.21

a) 5d, five
b) 1s, one
c) 6f, seven
d) 2p, three
Mon Oct 15, 2018 2:29 pm
Forum: General Science Questions
Topic: BruinCast [ENDORSED]
Replies: 4
Views: 448

### Re: BruinCast[ENDORSED]

if i remember correctly on the first day of class he said he doesn't bruin cast his lectures unfortunately
Sun Oct 07, 2018 11:48 pm
Forum: Balancing Chemical Reactions
Topic: L. 31
Replies: 2
Views: 341

### L. 31

The compound XCl2(NH3)2 can be formed by reacting XCl4 with NH3. Suppose that 3.571 g of XCl4 reacts with excess NH3 to give Cl2 and 3.180 g of XCl2(NH3)2. What is the element X?

I've been having trouble balancing the equation and identifying the mass of X?
Sun Oct 07, 2018 11:44 pm
Forum: Balancing Chemical Reactions
Topic: 7th edition L.35
Replies: 5
Views: 413

### Re: 7th edition L.35

the final balanced equation should be Fe3Br8 + 4Na2CO3 --> 8NaBr + 4CO2 + Fe3O4
Sun Oct 07, 2018 10:48 pm
Forum: Significant Figures
Topic: Atlantic Pacific Rule
Replies: 2
Views: 986

### Re: Atlantic Pacific Rule

the rule states that if there is an Absence of a decimal point, you start counting from the right side of the number, and if there is a Presence of a decimal point you start counting from the left side of the number to determine how many significant figures there are overall.