Search found 104 matches
- Sun Mar 15, 2020 1:59 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Electrodes of Concentration Cell
- Replies: 3
- Views: 324
Re: Electrodes of Concentration Cell
The cathode is the negative electrode.
- Sun Mar 15, 2020 1:58 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst K vs Q
- Replies: 14
- Views: 1032
Re: Nernst K vs Q
You use K when the reaction is at equilibrium and Q if it is not.
- Sun Mar 15, 2020 1:57 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: spontaneity
- Replies: 4
- Views: 506
Re: spontaneity
You determine the value of delta G, and if it is negative, then it is spontaneous
- Sun Mar 15, 2020 1:55 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: lnQ
- Replies: 22
- Views: 1463
Re: lnQ
Yes, raise the coefficients as the power
- Sun Mar 15, 2020 1:55 pm
- Forum: Calculating Work of Expansion
- Topic: reversible expansion
- Replies: 4
- Views: 415
Re: reversible expansion
It represents work done by expansion
- Sun Mar 08, 2020 9:13 pm
- Forum: Zero Order Reactions
- Topic: Zero Order Rxn
- Replies: 7
- Views: 876
Re: Zero Order Rxn
Yes, zero order reactions do not need any other factors, only the rate constant.
- Sun Mar 08, 2020 9:12 pm
- Forum: General Rate Laws
- Topic: Rate limiting step
- Replies: 12
- Views: 878
Re: Rate limiting step
The rate limiting step is the slowest step of a chemical reaction that determines the rate at which the overall reaction proceeds.
- Sun Mar 08, 2020 9:10 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: pre-exponential factor
- Replies: 3
- Views: 254
Re: pre-exponential factor
A is the frequency of collisions in the correct orientation.
- Sun Mar 08, 2020 9:08 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Where do we find the values for A?
- Replies: 5
- Views: 496
Re: Where do we find the values for A?
A is the frequency of collisions. You can calculate A using the Arrhenius equation given the other variables, including temperature, activation energy, and equilibrium constant.
- Sun Mar 08, 2020 9:04 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Exothermic vs. Endothermic
- Replies: 14
- Views: 990
Re: Exothermic vs. Endothermic
It is an exothermic reaction when the activation energy of the reactants are higher than the products. If the activation energy of the products is higher than the reactants, then it is an endothermic reaction.
- Sun Mar 08, 2020 9:02 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Molecularity
- Replies: 12
- Views: 844
Re: Molecularity
Molecularity is the number of molecules or ions that participate in the rate determining step.
- Sat Feb 29, 2020 10:44 pm
- Forum: Balancing Redox Reactions
- Topic: Reducing/Oxidizing Agents
- Replies: 13
- Views: 647
Re: Reducing/Oxidizing Agents
Oxidizing agents are the ones that oxidize, so the remove electrons, while reducing agents are the ones doing the reducing, so they provide the electrons.
- Sat Feb 29, 2020 10:41 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: platinum
- Replies: 5
- Views: 418
Re: platinum
Yes, you use platinum if no metals are given as your conductor.
- Sat Feb 29, 2020 10:40 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode vs Cathode
- Replies: 5
- Views: 377
Re: Anode vs Cathode
The anode is the one being oxidized, which means it is losing electrons, while the cathode is being reduced, which means it is gaining electrons.
- Sat Feb 29, 2020 10:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: No Salt Bridge
- Replies: 7
- Views: 563
Re: No Salt Bridge
The anode is losing electrons, making it gain a more positive charge, while the cathode is gaining electrons making it have a more negative charge.
- Sat Feb 29, 2020 10:36 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt bridges
- Replies: 11
- Views: 785
Re: Salt bridges
The purpose of a salt bridge is to balance the charges between the half cells. The electrons flow from the anode to the cathode.
- Sun Feb 23, 2020 2:43 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode vs Cathode
- Replies: 6
- Views: 405
Re: Anode vs Cathode
The cathode is where the species are reduced and anode is where the species are oxidized.
- Sun Feb 23, 2020 2:40 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in -nFE
- Replies: 12
- Views: 904
Re: n in -nFE
n is the number of moles of electrons in a balanced half reaction.
- Sun Feb 23, 2020 2:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: positive E naught
- Replies: 2
- Views: 177
Re: positive E naught
When E is positive, then delta G is negative, which makes the reaction spontaneous and favorable.
- Sun Feb 23, 2020 2:36 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidizing/Reducing Agents
- Replies: 11
- Views: 842
Re: Oxidizing/Reducing Agents
Oxidizing agents are the ones that oxidize, so the remove electrons, while reducing agents are the ones doing the reducing, so they provide the electrons.
- Sun Feb 23, 2020 2:34 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: salt bridge
- Replies: 5
- Views: 345
Re: salt bridge
The purpose of a salt bridge is to balance the charges between the half cells. The electrons flow from the anode to the cathode.
- Sun Feb 16, 2020 8:19 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneous
- Replies: 13
- Views: 832
Re: Spontaneous
A spontaneous reaction has a delta G value that is negative (G<0)
- Sun Feb 16, 2020 8:14 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K
- Replies: 12
- Views: 746
Re: K
To calculate K, use gases and aqueous solutions but not solids or liquids.
- Sun Feb 16, 2020 8:13 pm
- Forum: Balancing Redox Reactions
- Topic: Oxygen and Hydrogen
- Replies: 4
- Views: 249
Re: Oxygen and Hydrogen
Hydrogen has an oxidation number of +1 when combined with nonmetals but has an oxidation number of -1 when combined with metals. Oxygen can have an oxidation number of -2, -1, or 0.
- Sun Feb 16, 2020 8:03 pm
- Forum: Balancing Redox Reactions
- Topic: Reduction vs. oxidation
- Replies: 29
- Views: 1244
Re: Reduction vs. oxidation
Oxidation is the loss of electrons and reduction is the gain of electrons. You can determine what is being reduced or oxidized is by the change in oxidation numbers of reactants and products.
- Sun Feb 16, 2020 8:00 pm
- Forum: Van't Hoff Equation
- Topic: Van't Hoff Equation
- Replies: 3
- Views: 201
Re: Van't Hoff Equation
The Van't Hoff Equation can be used to calculate K at different temperatures if enthalpy of reaction is known. It relates the change in equilibrium constant of a chemical reaction to the change in temperature.
- Sat Feb 08, 2020 12:14 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Addition of a solid product/reactant
- Replies: 3
- Views: 250
Re: Addition of a solid product/reactant
Equilibrium will not shift because it only take into account gases and aqueous solution not liquids or solids.
- Sat Feb 08, 2020 12:12 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Delta H and qp
- Replies: 8
- Views: 213
Re: Delta H and qp
ΔH = qp when pressure is constant.
- Sat Feb 08, 2020 12:10 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard enthalpies of formation
- Replies: 5
- Views: 140
Re: Standard enthalpies of formation
Yes, balance the equation and the multiply the standard enthalpy of formation of products and reactants by their stoichiometric coefficients.
- Sat Feb 08, 2020 12:08 pm
- Forum: Calculating Work of Expansion
- Topic: Units for -PV
- Replies: 5
- Views: 200
Re: Units for -PV
For pressure use atm, then for the overall answer you would get L atm and convert those units to joules using 1 L atm = 101.325 J
- Sat Feb 08, 2020 12:06 pm
- Forum: Calculating Work of Expansion
- Topic: Constant Volume and Pressure Values
- Replies: 8
- Views: 366
Re: Constant Volume and Pressure Values
I think it would be good for you to remember them, especially monoatomic ones.
- Sun Feb 02, 2020 7:03 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Closed vs isolated systems
- Replies: 24
- Views: 941
Re: Closed vs isolated systems
In a closed system, the matter within the system is constant but energy can be transferred from the system to surroundings and vice versa. In an isolated system, neither matter nor energy between system and surroundings are allowed.
- Sun Feb 02, 2020 7:00 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: extensive property
- Replies: 12
- Views: 697
Re: extensive property
An extensive property is a property that changes when the amount of matter changes. Examples include mass, volume, and internal energy.
- Sun Feb 02, 2020 6:55 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Delta U = Q
- Replies: 8
- Views: 222
Re: Delta U = Q
When W = 0 there is constant volume, in which there is no expansion or compression because that is when work is done.
- Sun Feb 02, 2020 6:50 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1 #6
- Replies: 6
- Views: 369
Re: Test 1 #6
HF is a weak acid and not a strong acid because it does not completely dissociate in water. The ions it forms during dissociation are too strongly bound to each other for it to be a strong acid.
- Sun Feb 02, 2020 6:44 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Constant Volume and Pressure
- Replies: 7
- Views: 298
Re: Constant Volume and Pressure
Constant volume and constant pressure means that the volume or pressure does not change during a reaction.
- Sun Jan 26, 2020 10:32 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Negative Square Root solving an ICE box
- Replies: 13
- Views: 604
Re: Negative Square Root solving an ICE box
You might have made a mistake because you should not have a negative number inside the square root. However, the overall answer when solving the quadratic formula can be positive and negative.
- Sun Jan 26, 2020 10:26 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 9
- Views: 462
Re: Hess's Law
Hess's Law states that regardless of the intermediate steps taken in a reaction, the total enthalpy change for the reaction is the sum of each individual changes.
- Sun Jan 26, 2020 10:25 pm
- Forum: Phase Changes & Related Calculations
- Topic: Hess's Law
- Replies: 8
- Views: 216
Re: Hess's Law
Hess's Law states that regardless of the intermediate steps taken in a reaction, the total enthalpy change for the reaction is the sum of each individual changes.
- Sun Jan 26, 2020 10:20 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Exothermic reaction
- Replies: 18
- Views: 753
Re: Exothermic reaction
If the reaction is exothermic, increase in temperature would cause the reaction to shift left and decrease in temperature would cause the reaction to shift right
- Sun Jan 26, 2020 10:15 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy
- Replies: 5
- Views: 193
Re: Enthalpy
Enthalpy is a state function because it only depends on initial and final values in the reaction. The path taken to get from the initial to final value does not matter.
- Sun Jan 26, 2020 10:13 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: endothermic
- Replies: 8
- Views: 354
Re: endothermic
If reaction is endothermic and there is an increase in temperature, the forward reaction (products) is favored and the equilibrium constant increases.
- Sun Jan 26, 2020 10:11 pm
- Forum: Ideal Gases
- Topic: Kc vs Kp
- Replies: 109
- Views: 5453
Re: Kc vs Kp
If the reaction consists of all gases then you would use Kp. Kc can be used for gases as well if the gases are given in concentration rather than pressure.
- Sun Jan 26, 2020 10:05 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Finding Ka from pH
- Replies: 5
- Views: 324
Re: Finding Ka from pH
If you're given pH or pOH then use [H3O+] = 10^-pH and [OH-] = 10^-pOH to determine concentration, and plug the concentrations into Ka/Kb formula to determine Ka/Kb value.
- Sun Jan 26, 2020 10:00 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pH
- Replies: 7
- Views: 296
Re: pH
You could convert pKa to Ka, then use Ka = 10^(-pKa). Use the Ka to find [H3O+]. Determine pH by this equation: pH = -log [H3O+].
- Sun Jan 26, 2020 9:55 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: ICE BOX
- Replies: 27
- Views: 924
Re: ICE BOX
You would X is too small when K < 10^3
- Fri Jan 10, 2020 4:09 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K expression involving solids/liquids
- Replies: 7
- Views: 305
Re: K expression involving solids/liquids
To determine the equilibrium constant, only gases and aqueous solutions are used. Liquids and solids are not used because pure substances do not change in a reaction.
- Fri Jan 10, 2020 4:06 pm
- Forum: Ideal Gases
- Topic: R in PV=nRT
- Replies: 34
- Views: 7096
Re: R in PV=nRT
R is the Ideal Gas Constant which has the value of 8.314J/molK.
- Fri Jan 10, 2020 4:04 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Pressure and Volume
- Replies: 8
- Views: 243
Re: Pressure and Volume
Changes in pressure and volume do not affect value of the equilibrium constant.
- Fri Jan 10, 2020 4:02 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: using Kp vs Kc
- Replies: 13
- Views: 1584
Re: using Kp vs Kc
Kp is for partial pressure, so when your products and reactants are in the gas phase. Kc is for concentration. However, for gases, you can use either Kc or Kp and just convert using the Ideal Gas Law.
- Fri Jan 10, 2020 3:47 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: K vs Q
- Replies: 9
- Views: 1793
Re: K vs Q
Q measures the relative amounts of products and reactant present during a reaction at a particular point in time. Q is compared to K, the equilibrium constant, to determine which direction the reaction proceeds. If Q>K, then the reverse reaction is favored and if Q<K, then the forward reaction is fa...
- Sun Dec 08, 2019 5:01 pm
- Forum: Resonance Structures
- Topic: Molecules with resonance
- Replies: 4
- Views: 512
Re: Molecules with resonance
Acids are stronger when there is resonance because the electrons are delocalized, in which the charges would be spread out more.
- Sun Dec 08, 2019 4:58 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentate
- Replies: 3
- Views: 330
Re: Polydentate
The ligand is polydentate if there are more than one lone pairs that the atom can donate to the transition metal it forms a coordination compound with.
- Sun Dec 08, 2019 4:57 pm
- Forum: Lewis Acids & Bases
- Topic: Mg(OH)2 Considered strong or weak base?
- Replies: 5
- Views: 3275
Re: Mg(OH)2 Considered strong or weak base?
Mg(OH)2 is a strong base because it is one of the Group 1 and 2 oxide and hydroxides, where those are strong bases.
- Sun Dec 08, 2019 4:55 pm
- Forum: Properties of Light
- Topic: Light acting like a wave
- Replies: 4
- Views: 401
Re: Light acting like a wave
Light acts like a wave when it forms diffraction patterns, in which there is interference in the waves. This was proven in the experiment where light passed through the opening of two slits and forms interference patterns on a screen. The bands were darker where it was between the spot between the s...
- Sun Dec 08, 2019 4:48 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 Bonding
- Replies: 2
- Views: 302
Re: Hydrogen Bonding
SO3 can form hydrogen bonds in water because it contains oxygen atoms, which can form a bond with hydrogen atom from the water molecule due to partial charges on the atoms.
- Sat Nov 30, 2019 11:40 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentate
- Replies: 3
- Views: 161
Re: Polydentate
A polydentate ligand has multiple lone pair donating sites that are bonded to a central atom.
- Sat Nov 30, 2019 11:37 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Shapes
- Replies: 3
- Views: 251
Re: Shapes
Tetrahedral shape is formed when there are four electron densities, which are four bonds with no lone pairs and square planar is formed when there are six electron densities, consisting of four bonds and two lone pairs.
- Sat Nov 30, 2019 11:31 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: salt and water formation
- Replies: 5
- Views: 355
Re: salt and water formation
When acid and base solutions react, they produce water and a neutral ionic compound, salt, which is composed of a cation (from the base) and and anion (from the acid).
- Sat Nov 30, 2019 11:21 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 1
- Views: 121
Re: Ligands
A ligand is an atom or molecule that binds to a metal ion through coordinate bonding.
- Sat Nov 30, 2019 11:20 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentate = more than one lone pair?
- Replies: 4
- Views: 277
Re: Polydentate = more than one lone pair?
A polydentate ligand has more than two lone pair donating sites that are used to bond to a central atom.
- Sun Nov 24, 2019 2:50 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent vs linear
- Replies: 56
- Views: 4389
Re: Bent vs linear
The bent shape has lone pair on the central atom while the linear shape typically does not have any lone pairs except for the exception of the molecule with 5 electron densities where there are 2 bonds and 3 lone pairs and the molecule with 6 electron densities with 2 bonds and 4 electron densities.
- Sun Nov 24, 2019 2:46 am
- Forum: Sigma & Pi Bonds
- Topic: Rotation
- Replies: 3
- Views: 244
Re: Rotation
Sigma bonds have their electron density along the bond axis, while pi bonds have their electron density above and below the bond axis. Therefore, the pi bonds cannot rotate like the sigma bonds because rotating would break the pi bond.
- Sun Nov 24, 2019 2:44 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: AXE formula
- Replies: 32
- Views: 12298
Re: AXE formula
It is possible to determine the molecular shape from AXE formula. The formula corresponds to the number of electron densities, including the lone pairs and bonds, which is then used to determine shape of the molecule.
- Sun Nov 24, 2019 2:42 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation Number
- Replies: 3
- Views: 313
Re: Oxidation Number
The oxidation number is the number of electrons that an atom gains or loses in order to form a chemical bond with another atom. It shows the total number of electrons that have been removed from an element (positive oxidation state) or added to an element (negative oxidation state) to get to its pre...
- Sun Nov 24, 2019 2:40 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-dipole in a solid phase vs gas phase
- Replies: 15
- Views: 1213
Re: dipole-dipole in a solid phase vs gas phase
Dipole-dipole in the solid phase is stronger because there are stronger attractions between molecules than in the gas phase.
- Sun Nov 17, 2019 9:58 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs on VSEPR Model
- Replies: 2
- Views: 150
Lone Pairs on VSEPR Model
How do you know if a lone pair lies on the axial or equatorial position?
- Sun Nov 17, 2019 9:54 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: intermolecular forces
- Replies: 2
- Views: 139
Re: intermolecular forces
Intermolecular forces are usually temporary such as instantaneous dipole-induced-dipole forces or London dispersion forces, which are forces caused by movements of the electrons in interacting molecules. Dipole-dipole forces are electrostatic interactions of permanent dipoles in molecules.
- Sun Nov 17, 2019 9:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Model
- Replies: 3
- Views: 195
Re: VSEPR Model
I think we will have to memorize the molecular shapes and bonds angles based off the Lewis structures.
- Sun Nov 17, 2019 9:44 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: covalent vs hydrogen bond?
- Replies: 2
- Views: 189
Re: covalent vs hydrogen bond?
Covalent bonds are formed when atoms within a molecule share electrons. Hydrogen bonding is when a partial positive charge of hydrogen atom of one molecule is attracted to another electronegative molecule (O, N, F). Intramolecular bonds are stronger than intermolecular forces, in which hydrogen bond...
- Sun Nov 17, 2019 9:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 4
- Views: 264
Bond Angles
How do you determine bond angles based off the molecular shape?
- Sun Nov 10, 2019 10:54 pm
- Forum: Sigma & Pi Bonds
- Topic: Occurance of Hybridization
- Replies: 1
- Views: 153
Re: Occurance of Hybridization
To determine hybridization, draw lewis dot structure and determine the steric number (the number of atoms bonded to a central atom plus the number of lone pairs attached to it) which will tell you the number of atomic orbitals needed to create a hybrid.
- Sun Nov 10, 2019 10:49 pm
- Forum: Bond Lengths & Energies
- Topic: Bond lengths and strength
- Replies: 4
- Views: 188
Re: Bond lengths and strength
Double bonds are stronger than single bonds, characterized by the sharing of four or six electrons between atoms. Double bonds are composed of sigma bonds between hybridized orbitals, and pi bonds between unhybridized p orbitals. Double bonds give additional stability to compounds.
- Sun Nov 10, 2019 10:46 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Oxidation Number
- Replies: 6
- Views: 431
Re: Oxidation Number
The oxidation number is the number of electrons that an atom gains or loses in order to form a chemical bond with another atom. It shows the total number of electrons that have been removed from an element (positive oxidation state) or added to an element (negative oxidation state) to get to its pre...
- Sun Nov 10, 2019 10:34 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: polarizability/polar power and bonds
- Replies: 2
- Views: 257
Re: polarizability/polar power and bonds
Polarizability results in distortion of the atom. If the degree of polarization is small, an ionic bond is formed, and if the degree of polarization is large, a covalent bond results. The ability of an atom is known as polar power, which is usually the cation, while the tendency of the anion to beco...
- Sun Nov 10, 2019 10:23 pm
- Forum: Ionic & Covalent Bonds
- Topic: Drawing hydrogen bonds between compounds?
- Replies: 1
- Views: 182
Re: Drawing hydrogen bonds between compounds?
Yes, that would be typically how you would draw hydrogen bonds. And just make sure that when you draw a hydrogen bond, it must be between a hydrogen atom with a partial positive charge of one molecule and a partial negative atom (either O, N, F) of another molecule.
- Sat Nov 02, 2019 10:27 pm
- Forum: Ionic & Covalent Bonds
- Topic: covalent character
- Replies: 3
- Views: 153
Re: covalent character
By having covalent character, there is partial sharing of electrons between atoms that have an ionic bond. The degree of ionic versus covalent character of a bond is determined by the difference in electronegativity between the atoms.
- Sat Nov 02, 2019 10:14 pm
- Forum: Coordinate Covalent Bonds
- Topic: Atom Sharing
- Replies: 5
- Views: 354
Re: Atom Sharing
I think the only difference between them is that coordinate covalent bonds share a pair of electrons and a covalent bonds shares one electron.
- Sat Nov 02, 2019 10:02 pm
- Forum: Lewis Structures
- Topic: Expanded Octet
- Replies: 3
- Views: 146
Expanded Octet
How do you know when a molecule has an expanded octet? Would you have to just guess and check by determining the formal changes in which it would have to be 0? For example SO3 and SO4. Are there certain elements that tend to have expanded octet?
- Sat Nov 02, 2019 9:50 pm
- Forum: Limiting Reactant Calculations
- Topic: Test 1 Question
- Replies: 5
- Views: 587
Re: Test 1 Question
You would convert the moles of water formed to moles of glucose using the balanced equation, then convert the amount you found to grams of glucose. After, you would subtract that from the grams of glucose initially present. To determine how many moles of O2 initially present, use the moles of H20 pr...
- Sat Nov 02, 2019 9:40 pm
- Forum: Empirical & Molecular Formulas
- Topic: Formula Units
- Replies: 2
- Views: 356
Re: Formula Units
To find molecules or formula units, you would use Avogadro's number to convert from moles.
- Sun Oct 27, 2019 9:02 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ionic v. Covalent
- Replies: 7
- Views: 258
Re: Ionic v. Covalent
Ionic bonds are formed when atoms lose or gain electrons and covalent bonds are formed when atoms share electrons. Ionic bonds are stronger than covalent bonds but in water, covalent bonds are stronger than ionic bonds, in which ionic bonds dissociate when in water.
- Sun Oct 27, 2019 9:00 pm
- Forum: Bond Lengths & Energies
- Topic: Lattice Energy
- Replies: 9
- Views: 464
Re: Lattice Energy
Lattice energy is the energy given off when oppositely charged ions in the gas phase come together to form a solid.
- Sun Oct 27, 2019 8:57 pm
- Forum: Electronegativity
- Topic: Polarity
- Replies: 5
- Views: 218
Re: Polarity
The polarity of a bond is determined by the electronegativities of the bonded atoms, in which electronegativity is the ability of an atom in a molecule to attract electrons to itself.
- Sun Oct 27, 2019 8:55 pm
- Forum: Resonance Structures
- Topic: Resonance Structures
- Replies: 4
- Views: 181
Resonance Structures
How do we know how many resonance structures a molecule has?
- Sun Oct 27, 2019 8:45 pm
- Forum: Trends in The Periodic Table
- Topic: Electronegativity vs. Electron affinity
- Replies: 8
- Views: 643
Re: Electronegativity vs. Electron affinity
The difference is that electronegativity is the ability of an atom to attract electrons towards itself while electron affinity is the amount of energy released when an atom gains an electron.
- Sun Oct 27, 2019 8:41 pm
- Forum: Ionic & Covalent Bonds
- Topic: What is the difference between an anion and cation?
- Replies: 7
- Views: 871
Re: What is the difference between an anion and cation?
An anion is an atom that accepts electrons making it have a negative charge and a cation is an atom that donates electrons making it positively charged. Usually cations are metals and nonmetals are anions. An example of a cation is Na+ and an example of an anion is Cl-.
- Sun Oct 20, 2019 6:23 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers
- Replies: 5
- Views: 352
Re: Quantum Numbers
The magnetic quantum number labels the different orientation of the orbitals in a subshell.
- Sun Oct 20, 2019 6:14 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Magnetic Quantum Number ml
- Replies: 5
- Views: 254
Re: Magnetic Quantum Number ml
An example would be how orbitals in p subshell could have orientation of px, py, or pz
- Sun Oct 20, 2019 6:12 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Magnetic Quantum Number ml
- Replies: 5
- Views: 254
Re: Magnetic Quantum Number ml
ml describes the different orbitals of a subshell, so the orientation.
- Sun Oct 20, 2019 6:08 pm
- Forum: *Shrodinger Equation
- Topic: Schrodinger’s Wave Function
- Replies: 3
- Views: 150
Re: Schrodinger’s Wave Function
In Schrodinger's Wave Function, the probability of finding an electron within the region of the atom is determined by squaring the wave function, ψ2, in which the wave function is a set of all the amplitudes.
- Sun Oct 20, 2019 6:00 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Stern and Gerlach
- Replies: 3
- Views: 177
Re: Stern and Gerlach
Spin up and spin down refers to the directions in which the electrons are moving. One electron could be spin up (positive spin) and the other would be spin down (negative spin).
- Sun Oct 20, 2019 5:47 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 3d vs 4s
- Replies: 2
- Views: 106
Re: 3d vs 4s
Electrons are removed from 4s first.
- Sun Oct 13, 2019 10:06 pm
- Forum: Properties of Electrons
- Topic: Photon
- Replies: 5
- Views: 171
Re: Photon
A photon is a particle of visible light.
- Sun Oct 13, 2019 10:02 pm
- Forum: DeBroglie Equation
- Topic: Detectable wavelike properties
- Replies: 1
- Views: 84
Detectable wavelike properties
Using the De Broglie equation, within what range would there be detectable wavelike properties?
- Sun Oct 13, 2019 9:58 pm
- Forum: Properties of Electrons
- Topic: Diffraction
- Replies: 2
- Views: 107
Re: Diffraction
Constructive interference is when the waves that meet are in the same direction, which could result in higher peaks. Destructive interference occurs when displacement of the waves that meet are in opposite directions; this could result in lower peaks.
- Sun Oct 13, 2019 9:45 pm
- Forum: Limiting Reactant Calculations
- Topic: Tricky Limiting Reagent Question
- Replies: 3
- Views: 273
Re: Tricky Limiting Reagent Question
You just need to convert the given amount of product to the amount of reactant of CO2 and determine whether the given amount of CO2 in the problem was more or less than what was used up in the reaction. If it was in excess, then the other reactant would have been the limiting reactant. If CO2 was th...
- Sun Oct 13, 2019 9:25 pm
- Forum: *Black Body Radiation
- Topic: Unit K in Wien's Law
- Replies: 2
- Views: 132
Re: Unit K in Wien's Law
K is the temperature in Kelvin and m refers to the wavelength.
- Sun Oct 06, 2019 5:25 pm
- Forum: Significant Figures
- Topic: Periodic table AMU values
- Replies: 2
- Views: 135
Re: Periodic table AMU values
I think it would be better to use the number of sig figs that are given in the problem rather than the one given by the periodic table.
- Sun Oct 06, 2019 5:20 pm
- Forum: Limiting Reactant Calculations
- Topic: How to determine limiting reactants
- Replies: 3
- Views: 163
Re: How to determine limiting reactants
Do you know which method is better or faster?