Search found 61 matches
- Sat Mar 16, 2019 10:46 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius Equation
- Replies: 3
- Views: 569
Arrhenius Equation
what is the A in the equation?
- Sat Mar 16, 2019 10:37 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: elementary steps
- Replies: 3
- Views: 672
elementary steps
Why can we use the stoichiometric coefficients as the order of reactants?
- Sat Mar 16, 2019 9:48 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalysts
- Replies: 4
- Views: 671
Catalysts
Are there any common catalysts we should know?
- Sun Mar 10, 2019 10:34 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: molecularity
- Replies: 8
- Views: 838
molecularity
what does it mean when something is bi-molecular, termolecular, etc.?
- Sun Mar 10, 2019 10:19 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Intermediate species
- Replies: 2
- Views: 376
Intermediate species
What is the significance of intermediate species?
- Sun Mar 10, 2019 9:50 pm
- Forum: First Order Reactions
- Topic: half life
- Replies: 2
- Views: 340
half life
In what situation would we use the half life equation?
- Sun Mar 03, 2019 7:30 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: kinetics and thermodynamics
- Replies: 4
- Views: 579
kinetics and thermodynamics
Which one is prevailant over the other in controlling a reaction? Are there certain conditions where thermodynamics control the reaction?
- Sun Mar 03, 2019 7:28 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: n and k
- Replies: 3
- Views: 416
n and k
Why do we need to determine n and k?
- Sun Mar 03, 2019 7:24 pm
- Forum: General Rate Laws
- Topic: Instantaneous vs unique
- Replies: 1
- Views: 207
Instantaneous vs unique
What is the difference between the instantaneous rate and the unique rate?
- Mon Feb 25, 2019 10:56 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Voltaic vs galvanic cell
- Replies: 2
- Views: 295
Voltaic vs galvanic cell
What's the difference between voltaic and galvanic cells?
- Sun Feb 24, 2019 9:25 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Signs of delta G and E
- Replies: 4
- Views: 486
Signs of delta G and E
For a spontaneous reaction, why does delta G have to be - and E have to be +?
- Sun Feb 24, 2019 9:23 pm
- Forum: Balancing Redox Reactions
- Topic: Work done
- Replies: 2
- Views: 308
Work done
How do you know if the work is done by the battery system?
- Sun Feb 24, 2019 9:18 pm
- Forum: Balancing Redox Reactions
- Topic: Salt bridge
- Replies: 1
- Views: 222
Salt bridge
What is the purpose of a salt bridge and a porous disc?
- Sun Feb 17, 2019 7:02 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Calculating entropy
- Replies: 5
- Views: 448
Calculating entropy
Why do we calculate entropy for volume change and temperature change independently?
- Sun Feb 17, 2019 7:00 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Intensive vs extensive
- Replies: 4
- Views: 494
Intensive vs extensive
Is gibbs free energy intensive or extensive?
- Sun Feb 17, 2019 6:58 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs free energy?
- Replies: 2
- Views: 313
Gibbs free energy?
What does Gibbs free energy measure?
- Sun Feb 10, 2019 3:41 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Spontaneous processes
- Replies: 2
- Views: 235
Spontaneous processes
Why is there an increase in entropy for any spontaneous process?
- Sun Feb 10, 2019 3:37 pm
- Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
- Topic: Residual entropy
- Replies: 2
- Views: 333
Residual entropy
How can you tell if a system has "low" residual entropy?
- Sun Feb 10, 2019 3:23 pm
- Forum: Calculating Work of Expansion
- Topic: Real processes
- Replies: 2
- Views: 337
Real processes
Why are all real processes irreversible?
- Sun Feb 03, 2019 6:07 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: 2nd law of thermodynamics
- Replies: 5
- Views: 575
2nd law of thermodynamics
Can someone explain the second law of thermodynamics and how it relates to what we are doing?
- Sun Feb 03, 2019 6:01 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: isolated vs closed system
- Replies: 7
- Views: 898
isolated vs closed system
What's the difference between an isolated system and a closed system?
- Sun Feb 03, 2019 5:51 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: finding W
- Replies: 6
- Views: 641
finding W
Is the integral formula equivalent to -P(V2-V1)? can you use both to find -P delta V?
- Sun Jan 27, 2019 4:18 pm
- Forum: Phase Changes & Related Calculations
- Topic: Steam
- Replies: 7
- Views: 689
Steam
Can someone explain why steam causes more severe burns than water? I'm still a bit confused on that
- Sun Jan 27, 2019 4:16 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's law vs bond enthalpies
- Replies: 1
- Views: 1065
Hess's law vs bond enthalpies
Will using either method yield the same answer? If not, which is the most accurate?
- Sun Jan 27, 2019 2:21 pm
- Forum: Phase Changes & Related Calculations
- Topic: Delta H
- Replies: 11
- Views: 2012
Delta H
What do positive and negative delta H mean?
- Sun Jan 20, 2019 2:33 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Removing products
- Replies: 10
- Views: 3938
Removing products
Would removing the products in an equilibrium reaction affect both Q and K or just Q?
- Sun Jan 20, 2019 2:18 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: 5% rule
- Replies: 4
- Views: 1512
5% rule
Is it always safe to assume that any Ka that is less than 10^-3 will result in an X that is less than 5%?
- Sun Jan 20, 2019 2:10 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Pressure
- Replies: 8
- Views: 780
Pressure
Does the equilibrium shift if pressure is changed? If so, why?
- Sat Jan 12, 2019 6:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Heterogeneous and homogeneous equilibria [ENDORSED]
- Replies: 8
- Views: 778
Heterogeneous and homogeneous equilibria [ENDORSED]
How are heterogeneous and homogeneous equilibria related to what we are learning?
- Sat Jan 12, 2019 6:15 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kp and Kc
- Replies: 1
- Views: 146
Kp and Kc
What is the difference/relationship between Kp and Kc?
- Sat Jan 12, 2019 6:07 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium constant
- Replies: 4
- Views: 403
Equilibrium constant
Why does adding more products or reactants not affect the equilibrium constant?
- Sun Dec 09, 2018 12:24 am
- Forum: Naming
- Topic: Chloro vs Chlorito
- Replies: 10
- Views: 1262
Chloro vs Chlorito
Is there a difference between the two? In class we use chloro but the book calls it chlorito.
- Sun Dec 09, 2018 12:11 am
- Forum: Hybridization
- Topic: Pi bonds
- Replies: 8
- Views: 1001
Pi bonds
Why are pi bonds always unhybridized?
- Sat Dec 08, 2018 8:49 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: Concentration
- Replies: 1
- Views: 335
Concentration
Is the concentration equivalent to the molarity of the substance?
- Sat Dec 08, 2018 8:32 pm
- Forum: Biological Examples
- Topic: Myoglobin and Hemoglobin
- Replies: 1
- Views: 421
Myoglobin and Hemoglobin
How many myoglobins make up a hemoglobin?
- Sat Dec 08, 2018 8:31 pm
- Forum: Biological Examples
- Topic: Cisplatin
- Replies: 7
- Views: 1322
Cisplatin
How does Cisplatin help in chemotherapy and why can't transplatin be used?
- Sun Dec 02, 2018 8:29 pm
- Forum: Naming
- Topic: Polydentate Ligands
- Replies: 2
- Views: 324
Polydentate Ligands
How can we tell if a ligand is polydentante?
- Mon Nov 26, 2018 8:12 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: Dipole-dipole and H bonding
- Replies: 1
- Views: 204
Dipole-dipole and H bonding
Can both dipole-dipole and H-bonding exist between two molecules?
- Mon Nov 26, 2018 7:48 pm
- Forum: Hybridization
- Topic: Atomic Orbitals
- Replies: 2
- Views: 127
Atomic Orbitals
What does it mean when it says "hybridization arises from atomic orbitals"?
- Mon Nov 26, 2018 5:22 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: T shaped
- Replies: 6
- Views: 588
T shaped
Why does AX3E2 make a T-shape and doesn't form a trigonal planar shape?
- Sun Nov 18, 2018 2:48 pm
- Forum: Sigma & Pi Bonds
- Topic: Amount of sigma bonds
- Replies: 6
- Views: 967
Amount of sigma bonds
In a bond between 2 atoms, can there only be one sigma bond? Are there any exceptions?
- Sun Nov 18, 2018 2:42 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Square Planar vs Tetrahedral
- Replies: 8
- Views: 2451
Square Planar vs Tetrahedral
What is the difference between square planar and tetrahedral? They both have 5 atoms but why are they different shapes?
- Sun Nov 18, 2018 2:29 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs
- Replies: 8
- Views: 2746
Lone Pairs
Can someone explain why lone pairs affect the shape of a molecule?
- Sun Nov 11, 2018 10:33 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Dipole-Induced Dipole [ENDORSED]
- Replies: 2
- Views: 216
Dipole-Induced Dipole [ENDORSED]
Can someone explain Dipole-Induced Dipole means? I am still unsure as to what it is.
- Sun Nov 11, 2018 10:30 am
- 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 Bonding [ENDORSED]
- Replies: 3
- Views: 391
Hydrogen Bonding [ENDORSED]
Why is Hydrogen Bonding generally stronger than other intermolecular forces?
- Sun Nov 11, 2018 10:27 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 4
- Views: 342
Molecular Shape
Is a molecule's shape solely dependent on the number of atoms involved? Do the type of atoms affect it?
- Sun Nov 04, 2018 12:46 am
- Forum: Lewis Structures
- Topic: Central Atom
- Replies: 3
- Views: 339
Central Atom
Is the central atom always the one with the lower ionization energy? Are there any exceptions?
- Sun Nov 04, 2018 12:44 am
- Forum: Octet Exceptions
- Topic: Copper
- Replies: 10
- Views: 993
Re: Copper
I believe it is that way because 3d9 has an unpaired electron which makes it unstable and 3d would rather have a full shell to stabilize it.
- Sun Nov 04, 2018 12:36 am
- Forum: Bond Lengths & Energies
- Topic: Bond Lengths [ENDORSED]
- Replies: 2
- Views: 349
Bond Lengths [ENDORSED]
Why do single bonds have longer bond lengths than double bonds?
- Sun Oct 28, 2018 4:24 pm
- Forum: Ionic & Covalent Bonds
- Topic: the Octet rule
- Replies: 21
- Views: 4155
the Octet rule
When forming bonds, do atoms always try to follow the octet rule? Are there exceptions to this rule/guideline?
- Sun Oct 28, 2018 1:36 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 4s and 3d [ENDORSED]
- Replies: 2
- Views: 324
4s and 3d [ENDORSED]
Why do we sometimes write the 4s orbital before including the 3d orbital?
- Sun Oct 28, 2018 1:30 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization Energy [ENDORSED]
- Replies: 7
- Views: 915
Ionization Energy [ENDORSED]
Why does ionization energy increase as you move to the right of the periodic table?
- Sun Oct 21, 2018 3:31 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Conceptual Question
- Replies: 2
- Views: 308
Re: Conceptual Question
Quantum numbers specify the size/shell, shape, orientation, and spin state of an electron.
Hope this helps.
Hope this helps.
- Sun Oct 21, 2018 2:35 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Shielding
- Replies: 5
- Views: 1162
Shielding
Can someone explain shielding and how it relates to multi electron atoms?
- Sun Oct 21, 2018 2:27 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers
- Replies: 3
- Views: 714
Quantum Numbers
Are quantum numbers always integers? Can they ever be decimals or fractions?
- Sun Oct 14, 2018 1:09 pm
- Forum: Properties of Electrons
- Topic: Photoelectric Experiment
- Replies: 9
- Views: 562
Photoelectric Experiment
I understand that a higher frequency, not a higher intensity, will be able to remove an electron. However, what I don't understand is why? Increasing intensity and increasing frequency are both forms of increasing energy.
- Sun Oct 14, 2018 1:00 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Planck's constant
- Replies: 7
- Views: 1495
Planck's constant
Can someone explain to me what Planck's constant means and how it relates to what we are learning?
- Sun Oct 14, 2018 12:50 pm
- Forum: Einstein Equation
- Topic: Frequency and Velocity
- Replies: 1
- Views: 135
Frequency and Velocity
Both frequency and velocity are denoted by the letter "v", how can we tell the difference and will they be specified on the tests?
- Fri Oct 05, 2018 5:43 pm
- Forum: Balancing Chemical Reactions
- Topic: States of Matter
- Replies: 11
- Views: 1063
States of Matter
When balancing a chemical equation do the states of matter, (s),(l),(g), and (aq), affect anything or are they just there to show what state of matter the reactants/products are?
- Fri Oct 05, 2018 4:42 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Rounding molar mass
- Replies: 4
- Views: 326
Rounding molar mass
Is it okay to round the molar mass of the elements while calculating something? If so, to what place do I round the molar mass to?
- Fri Oct 05, 2018 4:35 pm
- Forum: Significant Figures
- Topic: knowing how many sig figs to use
- Replies: 17
- Views: 2235
knowing how many sig figs to use
I am still a bit confused on significant figures and when to use a certain number of sig figs. Will the answer to a problem always have the same number of sig figs as in the question?