Q: What do you call a tooth in a glass of water?
A: A one molar solution.
Search found 50 matches
- Wed Mar 14, 2018 11:23 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
- Wed Mar 14, 2018 11:22 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Elementary reactions
- Replies: 6
- Views: 848
Re: Elementary reactions
Elementary reactions are the steps within an overall reaction; the slowest one in a reaction mechanism provides the overall rate law!
- Wed Mar 14, 2018 11:19 pm
- Forum: General Rate Laws
- Topic: Unimolecular
- Replies: 5
- Views: 778
Re: Unimolecular
Unimolecular would be:
A--> P
Bimolecular could be:
A+A-->P
A+B-->P
A--> P
Bimolecular could be:
A+A-->P
A+B-->P
- Sun Mar 11, 2018 2:08 pm
- Forum: Second Order Reactions
- Topic: Differential vs Integrated
- Replies: 4
- Views: 867
Re: Differential vs Integrated
If you are given the concentration and time, use integrated rate law.
- Sun Mar 11, 2018 2:07 pm
- Forum: First Order Reactions
- Topic: Log vs ln
- Replies: 9
- Views: 1182
Re: Log vs ln
There isn't a need to convert from ln to log, especially because when integrated, the first order reaction provides ln.
- Sun Mar 11, 2018 2:05 pm
- Forum: Zero Order Reactions
- Topic: zero order rate?
- Replies: 14
- Views: 1521
Re: zero order rate?
This is true; rate is independent of concentration, as the differential rate law is rate=k ([A]^0=1).
- Mon Feb 26, 2018 1:43 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
Re: Post All Chemistry Jokes Here
Q: What did the chemist say when he found two isotopes of helium?
A: HeHe
A: HeHe
- Mon Feb 26, 2018 1:40 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: E of a Redox [ENDORSED]
- Replies: 5
- Views: 960
Re: E of a Redox [ENDORSED]
E is intensive, so the amount does not affect its potential.
- Mon Feb 26, 2018 1:39 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Trends in Increasing Reducing Ability
- Replies: 5
- Views: 820
Re: Trends in Increasing Reducing Ability
The more negative in potential, the more likely the substance is to be oxidized/work as a reducing agent. Therefore it has more of a reducing power.
- Mon Feb 26, 2018 1:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: When do you need to include Pt? [ENDORSED]
- Replies: 5
- Views: 663
Re: When do you need to include Pt? [ENDORSED]
If there is no solid metal state that works as the conducting electrode, you need a stable metal such as Pt to use.
- Mon Feb 26, 2018 1:35 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst Equation to find pH
- Replies: 6
- Views: 9986
Re: Nernst Equation to find pH
you change the lnQ to 2.303logQ, as they are equivalent, and plug that into the equation. The -log[H+] will be the pH.
- Mon Feb 26, 2018 1:32 pm
- Forum: Balancing Redox Reactions
- Topic: Cell Diagram [ENDORSED]
- Replies: 7
- Views: 826
Re: Cell Diagram [ENDORSED]
The phases are separated.
- Mon Feb 26, 2018 1:29 pm
- Forum: Balancing Redox Reactions
- Topic: Identifying Oxi/Red Agents [ENDORSED]
- Replies: 6
- Views: 992
Re: Identifying Oxi/Red Agents [ENDORSED]
The reducing agent/the component with reducing power is being oxidized and vice versa.
- Mon Feb 26, 2018 1:28 pm
- Forum: Balancing Redox Reactions
- Topic: Water in balancing reactions
- Replies: 4
- Views: 518
Re: Water in balancing reactions
Yes, it is used to balance out oxygens and the hydrogens in redox reactions.
- Mon Feb 26, 2018 1:14 pm
- Forum: Balancing Redox Reactions
- Topic: Recognizing a redox reaction in acidic or basic solution
- Replies: 5
- Views: 601
Re: Recognizing a redox reaction in acidic or basic solution
Yes, I'm pretty sure acidic or basic will be given.
- Sat Feb 03, 2018 2:33 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Extensive/Intensive Property [ENDORSED]
- Replies: 4
- Views: 565
Re: Extensive/Intensive Property [ENDORSED]
Intensive properties do not depend on quantity while extensive do. Intensive are preferred because they are more standardized.
- Sat Feb 03, 2018 2:32 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Isobaric [ENDORSED]
- Replies: 3
- Views: 544
Re: Isobaric [ENDORSED]
Isobaric means constant pressure.
- Sat Feb 03, 2018 2:29 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Assume ideal gas?
- Replies: 4
- Views: 540
Re: Assume ideal gas?
Yes, I think we assume ideal gases unless specified differently.
- Sat Feb 03, 2018 2:27 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
Re: Post All Chemistry Jokes Here
How about the chemical workers… are they unionized?
- Sat Feb 03, 2018 2:26 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
Re: Post All Chemistry Jokes Here
H2O is water and H2O2 is hydrogen peroxide. What is H2O4?
Drinking.
Drinking.
- Sat Feb 03, 2018 2:26 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
Re: Post All Chemistry Jokes Here
Did you know that you can cool yourself to -273.15˚C and still be 0k?
- Sat Feb 03, 2018 2:22 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: When to use Q versus K [ENDORSED]
- Replies: 6
- Views: 2565
Re: When to use Q versus K [ENDORSED]
Q is the reaction quotient while K is the equilibrium constant. You use K at equilibrium or when delta G is equal to 0. You use Q when delta G is not equal to 0.
- Sat Feb 03, 2018 2:20 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: What does it mean for a reaction to be "thermodynamically favored?"
- Replies: 6
- Views: 31257
Re: What does it mean for a reaction to be "thermodynamically favored?"
Thermodynamically favorable means spontaneous, or that the reaction does not require energy in order to happen.
- Sat Feb 03, 2018 2:18 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Homework 9.5 [ENDORSED]
- Replies: 11
- Views: 1183
Re: Homework 9.5 [ENDORSED]
Its based on system vs. surroundings and where the heat is transferring. Because heat goes from hot to cold, the 800 K part is losing and has a negative sign while the 200 K is gaining and has a positive sign.
- Sat Feb 03, 2018 2:17 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: 9.7
- Replies: 7
- Views: 677
Re: 9.7
We just need to know that its for a monatomic ideal gas atom. The C=5/2 R is on the formula sheet if I remember correctly!
- Sat Feb 03, 2018 2:03 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Difference between systems? [ENDORSED]
- Replies: 8
- Views: 1023
Re: Difference between systems? [ENDORSED]
An open system can transfer matter and/or energy. A closed system system can transfer energy not matter. An isolated system cannot transfer either.
- Sat Feb 03, 2018 2:01 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: ideal cooler [ENDORSED]
- Replies: 5
- Views: 577
Re: ideal cooler [ENDORSED]
Ideal means no heat or matter transfer between system and surroundings, so the system is isolated.
- Fri Jan 12, 2018 4:08 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2759492
Re: Post All Chemistry Jokes Here
Why did the acid go to the gym?
To become a buffer solution!
To become a buffer solution!
- Fri Jan 12, 2018 4:00 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat Capacity vs. Specific Heat Capacity
- Replies: 6
- Views: 1016
Re: Heat Capacity vs. Specific Heat Capacity
Heat Capacity is the amount of heat required to raise the temperature of an object by 1 deg C and is extensive. However, specific heat capacity is intensive and is the amount of heat required to raise the temperature of 1 gram of a substance by 1 deg C. Specific heat is preferred over heat capacity.
- Fri Jan 12, 2018 3:49 pm
- Forum: Phase Changes & Related Calculations
- Topic: Intensive vs. Extensive
- Replies: 5
- Views: 2114
Re: Intensive vs. Extensive
Intensive properties do not depend on amount of the substance while extensive properties do. An example of an intensive property is density, while extensive include work and heat. For calculations, an extensive divided by an extensive gives an intensive property, which is seen with heat capacity and...
- Mon Dec 04, 2017 3:27 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q [ENDORSED]
- Replies: 7
- Views: 1098
Re: Q [ENDORSED]
Q is the reaction quotient and represents the ratio of products and reactants at any point within reaction. When compared to K it provides insight into how the reaction will go.
- Mon Dec 04, 2017 3:20 pm
- Forum: Ideal Gases
- Topic: Units of Partial Pressure
- Replies: 7
- Views: 952
Re: Units of Partial Pressure
Partial pressures are in atm.
- Mon Dec 04, 2017 3:19 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Table 11.2
- Replies: 4
- Views: 510
Re: Table 11.2
K=Kp which is for gases and partial pressures but Kc is for molarity.
- Mon Dec 04, 2017 3:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ch 11
- Replies: 3
- Views: 525
Re: ch 11
Due to what is given, one must find the molarity so you have to divide by the volume to get it.
- Mon Nov 27, 2017 1:27 pm
- Forum: Ideal Gases
- Topic: R in PV=nRT [ENDORSED]
- Replies: 7
- Views: 1683
Re: R in PV=nRT [ENDORSED]
R is the ideal gas constant, and its value depends on the units of P, V, n, and T within the ideal gas law.
- Mon Nov 27, 2017 1:21 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs vs. Bonding Pairs
- Replies: 6
- Views: 863
Re: Lone Pairs vs. Bonding Pairs
Lone pairs take up more space that bonding pairs, which leads them to have greater repulsion.
- Mon Nov 27, 2017 1:21 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs [ENDORSED]
- Replies: 3
- Views: 454
Re: Lone Pairs [ENDORSED]
No, it doesn't affect the shape.
- Mon Nov 27, 2017 1:19 pm
- Forum: Hybridization
- Topic: Pi Bonds vs. Sigma Bonds
- Replies: 7
- Views: 1038
Re: Pi Bonds vs. Sigma Bonds
Single bonds are sigma bonds. Double bonds are a sigma bond and a pi bond. Triple bonds are a sigma bond and 2 pi bonds.
- Mon Nov 13, 2017 8:04 pm
- Forum: Hybridization
- Topic: Filling electron shells [ENDORSED]
- Replies: 3
- Views: 590
Re: Filling electron shells [ENDORSED]
4s is lower in energy than 3d, so it gets filled up first.
- Mon Nov 13, 2017 8:02 pm
- Forum: Hybridization
- Topic: Writing out the Hybridization [ENDORSED]
- Replies: 4
- Views: 681
Re: Writing out the Hybridization [ENDORSED]
The number of e- density areas equal the hybridization. So for example, a molecule with 1 s and 1 p would have 2 hybridized orbitals and a hybridization of sp.
- Mon Nov 06, 2017 4:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Midterm
- Replies: 8
- Views: 884
Re: Midterm
No, it covers fundementals through chapter 3, so the latest thing covered is resonance/bonds.
- Mon Nov 06, 2017 4:57 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 3
- Views: 323
Re: Bond Angles
It's dependent on the structure, so it would help to visualize the structure and use it to approximate bond angles.
- Mon Nov 06, 2017 4:55 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Magnetic Quantum Number
- Replies: 6
- Views: 1011
Re: Magnetic Quantum Number
The range for ml is -l to l, so its dependent on the subshell (l) of the element.
- Mon Nov 06, 2017 4:54 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electron Spin Quantum Number [ENDORSED]
- Replies: 12
- Views: 3982
Re: Electron Spin Quantum Number [ENDORSED]
the quantum spin number can haven either +/- 1/2.
- Mon Nov 06, 2017 4:52 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: trigonal pyramidal
- Replies: 3
- Views: 469
Re: trigonal pyramidal
Trigonal pyramidal is three bonding pairs and one lone pair.
- Sat Oct 28, 2017 4:30 pm
- Forum: Lewis Structures
- Topic: Lewis Structures- resonance [ENDORSED]
- Replies: 4
- Views: 412
Re: Lewis Structures- resonance [ENDORSED]
For resonance, you draw all of the possible structures and connect them by showing resonance through double sided arrows (<---->).
- Sat Oct 28, 2017 4:28 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge of 0 [ENDORSED]
- Replies: 3
- Views: 2746
Re: Formal Charge of 0 [ENDORSED]
A formal charge of 0 is the most favorable because it is the most stable.
- Sat Oct 28, 2017 4:27 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: How to figure out formal charge? [ENDORSED]
- Replies: 6
- Views: 1798
Re: How to figure out formal charge? [ENDORSED]
Formal charge is found by the formula FC= V - (L+(s/2)) where v is the amount of valence electrons of the atom, L is the amount of lone pair electrons, and s/2 is the amount of bonds shared, which can be figured out by divided the electrons shared by 2.
- Sun Oct 22, 2017 2:16 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Balmer/Lyman Series [ENDORSED]
- Replies: 7
- Views: 911
Re: Balmer/Lyman Series [ENDORSED]
Balmer is when an electron jumps down to n=2 from a higher energy level and Lyman is when it jumps down to n=1.
- Sun Oct 22, 2017 2:10 pm
- Forum: DeBroglie Equation
- Topic: Should velocity always be in m.s. when solving? [ENDORSED]
- Replies: 11
- Views: 1893
Re: Should velocity always be in m.s. when solving? [ENDORSED]
Velocity should always be in m/s with chemistry calculations.