Search found 134 matches
- Thu Mar 11, 2021 6:21 pm
- Forum: *Enzyme Kinetics
- Topic: Catalysts in a reaction
- Replies: 12
- Views: 1624
Re: Catalysts in a reaction
Yes, catalysts always go from reactant to product and not the other way around
- Thu Mar 11, 2021 6:20 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Sapling 15
- Replies: 2
- Views: 196
Sapling 15
Calculate the activation energy, Ea , in kilojoules per mole for a reaction at 70.0 ∘C that has a rate constant of 0.201 s−1 and a frequency factor of 6.04×1011 s−1 .
I am not sure where to begin with this one if anyone can help
I am not sure where to begin with this one if anyone can help
- Thu Mar 11, 2021 6:19 pm
- Forum: Second Order Reactions
- Topic: Graphs
- Replies: 9
- Views: 729
Re: Graphs
1st order: reaction will have a straight-line graph of ln[A] v. t
2nd order: reaction will have a straight-line graph of 1/[A] v. t
Zero order: reaction will have a straight-line graph of [A] v. t
Note that 1st and Zero have negative slope whereas 2nd is positive
2nd order: reaction will have a straight-line graph of 1/[A] v. t
Zero order: reaction will have a straight-line graph of [A] v. t
Note that 1st and Zero have negative slope whereas 2nd is positive
- Thu Mar 11, 2021 6:18 pm
- Forum: First Order Reactions
- Topic: sapling week 10 #11
- Replies: 5
- Views: 316
Re: sapling week 10 #11
This is a first order reaction, so use the integrated law for first-order reactions: [A]= [A]0 e^-kt to solve for t. Also make sure that your units are correct because the answer is in minutes, not seconds.
- Thu Mar 11, 2021 6:16 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Sapling 14
- Replies: 2
- Views: 830
Sapling 14
A certain reaction has an activation energy of 41.43 kJ/mol. At what Kelvin temperature will the reaction proceed 4.50 times faster than it did at 343 K?
I am not sure what the k1 and k2 values would be here. I am trying to use the Arrhenius equation if anyone can help
I am not sure what the k1 and k2 values would be here. I am trying to use the Arrhenius equation if anyone can help
- Tue Mar 02, 2021 8:44 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode/Cathode
- Replies: 45
- Views: 1427
Re: Anode/Cathode
Anode goes on the left and cathode goes on the right
- Tue Mar 02, 2021 8:43 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: To Pt(s) or not to Pt(s)? - cell diagrams
- Replies: 6
- Views: 392
Re: To Pt(s) or not to Pt(s)? - cell diagrams
The only time you use platinum is when there is not a conducting solid in the redox reaction, in this case you add Pt(s)
- Tue Mar 02, 2021 8:42 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Textbook 6M7
- Replies: 4
- Views: 344
Textbook 6M7
Arrange the following metals in order of increasing strength as reducing agents for species in aqueous solution: (a) Cu, Zn, Cr, Fe; (b) Li, Na, K, Mg; (c) U, V, Ti, Al; (d) Ni, Sn, Au, Ag.
Does anyone know what the rule for this is?
Does anyone know what the rule for this is?
- Tue Mar 02, 2021 8:40 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Textbook 6M1
- Replies: 1
- Views: 144
Textbook 6M1
A student was given a standard Cu(s)|Cu2+(aq) half-cell and another half-cell containing an unknown metal M in 1.00 M M(NO3)2(aq) and formed the cell M(s)|M+(aq)||Cu2+(aq)|Cu(s). The cell potential was found to be −0.689 V. What is the value of E°(M2+/M)? I am not sure where to begin with this one i...
- Tue Mar 02, 2021 8:37 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Textbook 6L5
- Replies: 3
- Views: 269
Textbook 6L5
Write the half-reactions, the balanced equation for the cell reaction, and the cell diagram for each of the following skeletal equations: b) Ce4+(aq) + I−(aq) →I2(s) + Ce3+(aq) I am struggling to write the cell diagram for this one and I am not sure when using Pt(s) is appropriate if anyone can help.
- Tue Mar 02, 2021 8:34 pm
- Forum: Balancing Redox Reactions
- Topic: Textbook 6L3
- Replies: 1
- Views: 137
Textbook 6L3
Write the half-reactions and the balanced equation for the cell reaction for each of the following galvanic cells:
(d) Pt(s)|O2(g)|H+(aq)∥OH−(aq)|O2(g)|Pt(s)
Can anyone help me with this problem?
(d) Pt(s)|O2(g)|H+(aq)∥OH−(aq)|O2(g)|Pt(s)
Can anyone help me with this problem?
- Tue Mar 02, 2021 8:32 pm
- Forum: Balancing Redox Reactions
- Topic: 6K3d
- Replies: 1
- Views: 156
6K3d
Balance each of the following skeletal equations by using oxidation and reduction half-reactions. All the reactions take place in acidic solution. Identify the oxidizing agent and reducing agent in each reaction. Reaction of chlorine in water: Cl2(g)→HClO(aq)+Cl2(g) I am having trouble balancing thi...
- Tue Feb 23, 2021 7:06 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Sapling 13
- Replies: 2
- Views: 170
Sapling 13
Which of the reagents would oxidize Cr to Cr3+ , but not Fe to Fe3+?
Does anyone know how to determine this? I am a bit lost
Does anyone know how to determine this? I am a bit lost
- Tue Feb 23, 2021 7:04 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling 3
- Replies: 1
- Views: 145
Sapling 3
For a particular redox reaction, Cr is oxidized to CrO2−4 and Fe3+ is reduced to Fe2+ . Complete and balance the equation for this reaction in basic solution. The phases are optional.
Can anyone help me with this, I am not sure what I am doing wrong.
Can anyone help me with this, I am not sure what I am doing wrong.
- Tue Feb 23, 2021 7:03 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt Bridge
- Replies: 30
- Views: 1292
Re: Salt Bridge
The salt bridge is there to make sure there is electrical neutrality in each half cell and if you do not have this then one side would be positive and the other negative.
- Tue Feb 23, 2021 7:01 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Voltage
- Replies: 4
- Views: 228
Re: Voltage
Voltage is the same as the maximum cell potential, not maximum work.
- Tue Feb 23, 2021 6:59 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cathodes vs Anodes
- Replies: 5
- Views: 299
Re: Cathodes vs Anodes
I always remember it that A comes before C in the alphabet and if you put the A on the left side this represents the anode going to the C on the right side cathode and the flow of the electrons is left to right
- Tue Feb 23, 2021 6:58 pm
- Forum: Balancing Redox Reactions
- Topic: "Leo" Oxidation Numbers
- Replies: 26
- Views: 1059
Re: "Leo" Oxidation Numbers
LEO is an acronym that helps with understanding oxidation. It stands for "Loss of Electrons Oxidation" so oxidation is when there is a loss of electrons
- Wed Feb 17, 2021 10:57 am
- 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: w
- Replies: 12
- Views: 748
Re: w
Yes, if looking in terms of per mol
- Wed Feb 17, 2021 10:57 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneity of a System
- Replies: 38
- Views: 2716
Re: Spontaneity of a System
It is spontaneous under conditions that result in a negative delta G
- Wed Feb 17, 2021 10:56 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: What does the d in dq mean
- Replies: 3
- Views: 341
Re: What does the d in dq mean
The notation of dq means a very small change in q over very small change in time. This is notation for integrals.
- Wed Feb 17, 2021 10:55 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: G° vs G
- Replies: 30
- Views: 2419
Re: G° vs G
G is not under standard conditions, whereas Gº is
- Wed Feb 17, 2021 10:54 am
- Forum: Van't Hoff Equation
- Topic: Entropy
- Replies: 18
- Views: 934
Re: Entropy
I agree i think it depends on what values you are given
- Thu Feb 11, 2021 12:02 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: sapling 18
- Replies: 5
- Views: 315
sapling 18
Calculate the equilibrium constant, K , at 25.0°C for each of the reactions. Use the thermodynamic information provided in the table. The first step in the synthesis of trichloromethane (chloroform) from natural gas (methane). CH4(g)+Cl2(g)↽−−⇀CH3Cl(g)+HCl(g) I am not sure how to do this, I have bee...
- Thu Feb 11, 2021 11:59 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: ΔG° vs ΔG
- Replies: 20
- Views: 731
Re: ΔG° vs ΔG
There is a difference, ΔG° refers to Gibbs free energy under standard conditions and ΔG is not under standard conditions
- Thu Feb 11, 2021 11:59 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Sapling 8
- Replies: 5
- Views: 272
Sapling 8
Calculate the standard molar entropy of vaporization of water at 60.0 °C , given that its standard molar entropy of vaporization at 100.0 °C is 109.0 J⋅K−1⋅mol−1 and the molar heat capacities at constant pressure for liquid water and water vapor are 75.3 J⋅K−1⋅mol−1 and 33.6 J⋅K−1⋅mol−1 , respective...
- Thu Feb 11, 2021 11:57 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Isothermal Reactions
- Replies: 26
- Views: 1171
Re: Isothermal Reactions
Yes, you can assume this because the temperature stays constant in isothermal reactions
- Thu Feb 11, 2021 11:56 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Sapling number 5
- Replies: 1
- Views: 110
Sapling number 5
The molar heat capacity for carbon monoxide at constant volume is CV, m=20.17 J/(K·mol) . A 12.00 -L fixed-volume flask contains CO(g) at a pressure of 8.00 kPa and a temperature of 25.0 °C. Assuming that carbon monoxide acts as an ideal gas and that its heat capacity is constant over the given temp...
- Sat Feb 06, 2021 1:56 pm
- Forum: Calculating Work of Expansion
- Topic: Sapling 15
- Replies: 6
- Views: 518
Sapling 15
Automobile airbags contain solid sodium azide, NaN3, that reacts to produce nitrogen gas when heated, thus inflating the bag.
2NaN3(s)⟶2Na(s)+3N2(g)
Calculate the value of work, w, for the system if 26.9 g NaN3 reacts completely at 1.00 atm and 22 ∘ C
Can anyone help me with this?
2NaN3(s)⟶2Na(s)+3N2(g)
Calculate the value of work, w, for the system if 26.9 g NaN3 reacts completely at 1.00 atm and 22 ∘ C
Can anyone help me with this?
- Wed Feb 03, 2021 1:28 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Sapling 17
- Replies: 2
- Views: 136
Sapling 17
An 80.0 g sample of a gas was heated from 25 ∘C to 225 ∘C. During this process, 346 J of work was done by the system and its internal energy increased by 8025 J. What is the specific heat of the gas?
I am not sure how to set up this problem, any help is greatly appreciated!
I am not sure how to set up this problem, any help is greatly appreciated!
- Wed Feb 03, 2021 1:27 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Negative Heat Capacities
- Replies: 9
- Views: 363
Re: Negative Heat Capacities
Heat capacity can never be negative because it is the heat required to raise the temperature of a substance by 1°C.
- Wed Feb 03, 2021 1:26 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Week 3/4 Sapling #9
- Replies: 13
- Views: 670
Re: Week 3/4 Sapling #9
For this you need to set up an equation where heat lost by the system =- heat absorbed by the system and use the q=mCdeltaT equation for both sides.
- Wed Feb 03, 2021 1:25 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Units
- Replies: 11
- Views: 359
Re: Units
The textbook uses J/gºC so I would use this.
- Wed Feb 03, 2021 1:23 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Sapling 10
- Replies: 2
- Views: 214
Sapling 10
An ice cube with a mass of 50.2 g at 0.0 ∘C is added to a glass containing 394 g of water at 45.0 ∘C . Determine the final temperature of the system at equilibrium. The specific heat capacity of water, Cs , is 4.184 J/g⋅∘C , and the standard enthalpy of fusion, ΔH∘fus , of water is 6.01×103 J/mol . ...
- Thu Jan 28, 2021 11:23 am
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy Reactions
- Replies: 13
- Views: 396
Re: Enthalpy Reactions
in this case, I do think that we need to consider phase changes as well
- Thu Jan 28, 2021 11:21 am
- Forum: Phase Changes & Related Calculations
- Topic: Define Phase Change
- Replies: 78
- Views: 4914
Re: Define Phase Change
A phase change is just any time that a substance changes from one phase to another
- Thu Jan 28, 2021 11:20 am
- Forum: Phase Changes & Related Calculations
- Topic: when to assume x is insignificant
- Replies: 86
- Views: 6393
Re: when to assume x is insignificant
I would assume this when x is lower than 10^-4
- Thu Jan 28, 2021 11:19 am
- Forum: Phase Changes & Related Calculations
- Topic: Endothermic v. Exothermic
- Replies: 139
- Views: 10333
Re: Endothermic v. Exothermic
Yes, this is true. Endothermic reactions will always have a + delta H, and exothermic reactions will always have a - delta H, this is the case for all
- Thu Jan 28, 2021 11:17 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: 4E.5, 4E.7
- Replies: 7
- Views: 570
Re: 4E.5, 4E.7
For these questions it is important to draw out all lewis structures in the correct way. Then you can use this to subtract the reactions bonds minus products
- Thu Jan 21, 2021 7:15 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Equilibrium Adjustments
- Replies: 10
- Views: 402
Re: Equilibrium Adjustments
This summarizes Le Chatelier’s Principle that basically means when you disturb a system, the system will reestablish equilibrium by either shifting towards the products or towards the reactants to minimize the change.
- Thu Jan 21, 2021 7:12 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Temperature
- Replies: 45
- Views: 1285
Re: Temperature
You need to know the sign of deltaH (whether the reaction is exothermic or endothermic) to determine this. This should be given to you in a problem.
- Thu Jan 21, 2021 7:11 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Weak vs. Strong Acids and Bases
- Replies: 9
- Views: 518
Re: Weak vs. Strong Acids and Bases
Unfortunately the only way to know whether something is a strong/weak acid/base is to memorize them!
- Thu Jan 21, 2021 7:10 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Textbook 6.B.3
- Replies: 3
- Views: 175
Textbook 6.B.3
A careless laboratory technician wants to prepare 200.0 mL of a 0.025 M HCl(aq) solution but uses a volumetric flask of volume 250.0 mL by mistake. (a) What would the pH of the desired solution have been? (b) What will be the actual pH of the solution as prepared? Does anyone know where to start wit...
- Thu Jan 21, 2021 6:52 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: textbook 6.A.19
- Replies: 4
- Views: 224
textbook 6.A.19
Calculate the molar concentration of OH− in solutions with the following molar concentrations of H3O+: (c) 3.1 mol⋅L−1?
For part C, I keep on trying to calculate the pH of the solution by putting -log(3.1) in my calculator, but I keep getting a negative result. Is anyone else having this problem?
For part C, I keep on trying to calculate the pH of the solution by putting -log(3.1) in my calculator, but I keep getting a negative result. Is anyone else having this problem?
- Thu Jan 21, 2021 6:40 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5.I.33
- Replies: 1
- Views: 78
5.I.33
A sample of ammonium carbamate of mass 25.0 g was placed in an evacuated flask of volume 0.250 L and kept at 25 °C. At equilibrium, 17.4 mg of CO2 was present. What is the value of Kc for the decomposition of ammonium carbamate into ammonia and carbon dioxide? Has anyone properly got this answer? My...
- Thu Jan 21, 2021 6:37 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5.I.35
- Replies: 2
- Views: 210
5.I.35
Consider the reaction 2NO(g)⇌N2(g)+O2(g). If the initial partial pressure of NO(g) is 1.0 bar, and p is the equilibrium partial pressure of N2(g) in bar, what is the correct equilibrium relation?
Does anyone know how to answer this question? The text book says the answer is K=p2/(1.0−2p)2
Does anyone know how to answer this question? The text book says the answer is K=p2/(1.0−2p)2
- Thu Jan 21, 2021 6:34 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5.39
- Replies: 1
- Views: 65
5.39
In an experiment, 0.020 mol NO2 was introduced into a flask of volume 1.00 L and the reaction 2NO2(g)⇌N2O4(g) was allowed to come to equilibrium at 298 K. (a) Using information in Table 5G.2, calculate the equilibrium concentrations of the two gases. (b) The volume of the flask is reduced to half it...
- Tue Jan 12, 2021 2:34 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kw= 1.0 x 10^-14
- Replies: 11
- Views: 1504
Re: Kw= 1.0 x 10^-14
This is just a given value that has been experimentally determined. 1.0 x 10^-14 for water at 25 degrees Celsius.
- Tue Jan 12, 2021 2:32 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Bars
- Replies: 8
- Views: 307
Bars
Are bars the same unit as atmospheres? Refering to question 4 on sapling
- Tue Jan 12, 2021 2:31 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Le Chatelier's Principle
- Replies: 9
- Views: 529
Re: Le Chatelier's Principle
LeChatlier's principle states that reactions want to minimize the effect of changes in conditions of a system at equilibrium. So if anything changes like pressure temperature volume ect. the reaction will do the most to make sure this change does not affect the system at equilibrium
- Tue Jan 12, 2021 2:29 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Left vs. Right
- Replies: 29
- Views: 969
Re: Left vs. Right
I think you can use either way to describe a shift!
- Tue Jan 12, 2021 2:28 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling 5
- Replies: 4
- Views: 186
Sapling 5
Consider the reaction of NH3 and I2 to give N2 and HI. 2NH3(g)+3I2(g)↽−−⇀N2(g)+6HI(g)K Using two or more of the given equations, determine the equilibrium constant, K , for the reaction of NH3 with I2. H2(g)+I2(g)↽−−⇀2HI(g)I2(g)↽−−⇀2I(g)N2(g)+3H2(g)↽−−⇀2NH3(g)H2(g)+Cl2(g)↽−−⇀2HCl(g)Ka=160Kb=2.1×10−3...
- Wed Jan 06, 2021 3:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Gas Constant (R)
- Replies: 12
- Views: 305
Re: Gas Constant (R)
In this class, R is 8.314 J·K^-1·mol^-1.
- Wed Jan 06, 2021 3:26 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: names for reaction quotient Q
- Replies: 19
- Views: 486
names for reaction quotient Q
Is Qp, Qc, and Q all the same reaction quotient? I am not sure if they all mean the same thing.
- Wed Jan 06, 2021 3:24 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K=1
- Replies: 6
- Views: 153
Re: K=1
The reason why this is rare is because when K=1 this means that the concentration of reactants to products is equal. This means that the reactants and products are equally stable, and this is not usually the case, thus making K=1 rare.
- Wed Jan 06, 2021 3:23 pm
- Forum: Ideal Gases
- Topic: PV=nRT
- Replies: 74
- Views: 4221
Re: PV=nRT
P = Pressure
V = Volume
n = number of moles
R = gas constant (in Kelvin)
T = Temperature (in Kelvin)
make sure all in right units
V = Volume
n = number of moles
R = gas constant (in Kelvin)
T = Temperature (in Kelvin)
make sure all in right units
- Wed Jan 06, 2021 3:22 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc vs Kp
- Replies: 4
- Views: 139
Re: Kc vs Kp
Both Kp and Kc are equilibrium constants, but they measure different things. Kp measures partial pressures and Kc measures concentrations.
- Wed Jan 06, 2021 3:21 pm
- Forum: Ideal Gases
- Topic: T variable in pv=nrt [ENDORSED]
- Replies: 38
- Views: 1548
Re: T variable in pv=nrt [ENDORSED]
It will always be in Kelvin. Be sure to make sure this is the value you have.
- Tue Dec 15, 2020 9:38 pm
- Forum: Air Pollution & Acid Rain
- Topic: Acid Rain Formula
- Replies: 6
- Views: 1702
Acid Rain Formula
Are there multiple equations for the reaction of acid rain?
- Tue Dec 15, 2020 9:33 pm
- Forum: Naming
- Topic: Ligand use -ate
- Replies: 18
- Views: 972
Re: Ligand use -ate
you use ate when the overall compound is negative. hope this helps!
- Tue Dec 15, 2020 9:32 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 8
- Views: 389
Re: Ligands
yes, a coordination compound can have multiple kinds of ligands bound.
- Tue Dec 15, 2020 9:31 pm
- Forum: Hybridization
- Topic: Hybridization of CO2
- Replies: 5
- Views: 376
Re: Hybridization of CO2
yes! that looks correct to me as well.
- Tue Dec 15, 2020 9:30 pm
- Forum: Hybridization
- Topic: Lone Pairs & Hybridization
- Replies: 6
- Views: 397
Re: Lone Pairs & Hybridization
yes. you should take into account lone pairs in hybridization. they are considered regions of electron density
- Tue Dec 15, 2020 9:28 pm
- Forum: Amphoteric Compounds
- Topic: Recognizing Amphoteric Compounds
- Replies: 9
- Views: 692
Re: Recognizing Amphoteric Compounds
I usually look and see if it has both a H and an overall negative charge.
- Sun Dec 13, 2020 10:26 am
- Forum: Sigma & Pi Bonds
- Topic: Delocalized and Localized Bonds
- Replies: 7
- Views: 1197
Re: Delocalized and Localized Bonds
I think that delocalized means that there are renosonce structures
- Sun Dec 13, 2020 10:24 am
- Forum: Air Pollution & Acid Rain
- Topic: Acid Rain
- Replies: 24
- Views: 3815
Re: Acid Rain
H2O (l) + CO2 (g) ⇌ H2CO3 (aq)
H2O can also interact with other compounds such as So4 to result in acid rain as well.
H2O can also interact with other compounds such as So4 to result in acid rain as well.
- Sun Dec 13, 2020 10:20 am
- Forum: Naming
- Topic: K[Cu(en)2 (CN)2 ]
- Replies: 7
- Views: 542
Re: K[Cu(en)2 (CN)2 ]
each Cn has a negative one charge for a total of negative two, K has one positive charge. Therefore for the overall compound to be nuetral it should be Cu(I)
- Sun Dec 13, 2020 10:18 am
- Forum: Hybridization
- Topic: hybridization
- Replies: 10
- Views: 709
Re: hybridization
There are four regions of electron density around the N (one lone pair and 3 bonds). Therefore this means that it is sp3 hybridized.
- Sun Dec 13, 2020 10:16 am
- Forum: Amphoteric Compounds
- Topic: Tricks for Determining
- Replies: 5
- Views: 355
Re: Tricks for Determining
I think about it as looking to see if there are two things both present: An availible H+ to be donated, and and overall negative charge.
- Sun Dec 13, 2020 10:15 am
- Forum: Naming
- Topic: [Ni(NH3)2O2]Br2
- Replies: 3
- Views: 360
Re: [Ni(NH3)2O2]Br2
What does the answer key say? I believe that o2 has a nuetral charge and each Br has -1 so it should be nickel with +2 charge
- Sun Dec 13, 2020 10:05 am
- Forum: Lewis Acids & Bases
- Topic: KA and pKA
- Replies: 19
- Views: 898
Re: KA and pKA
Ka is the acid dissociation constant. pKa is the negative log of the Ka value. When Ka increases the strength of the acid also increases and the pka decreases.
- Mon Dec 07, 2020 2:22 pm
- Forum: Lewis Acids & Bases
- Topic: sapling #6
- Replies: 19
- Views: 876
Re: sapling #6
The CH3COOH has a carboxyl group COOH. This helps in determining that it a weak acid.
- Mon Dec 07, 2020 2:21 pm
- Forum: Conjugate Acids & Bases
- Topic: Conjugate Acids and Bases
- Replies: 4
- Views: 188
Conjugate Acids and Bases
How exactly do we find the conjugate acid and base for a species? Do all species have these?
- Mon Dec 07, 2020 2:19 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: pH vs pOH
- Replies: 9
- Views: 355
Re: pH vs pOH
Yes, if the pH is less than 7, it is acidic, and above 7 it is basic
You can find the pH from the pOH using the formula: 14 = pH + pOH
You can find the pH from the pOH using the formula: 14 = pH + pOH
- Mon Dec 07, 2020 2:18 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Sapling Week 10 question
- Replies: 6
- Views: 201
Re: Sapling Week 10 question
pH + pOH = 14
pH = -log([H+])
pOH = -log9[OH-])
[H+] = 10^-pH
[OH-] = 10^-pOH
I hope this helps!
pH = -log([H+])
pOH = -log9[OH-])
[H+] = 10^-pH
[OH-] = 10^-pOH
I hope this helps!
- Mon Dec 07, 2020 2:16 pm
- Forum: Conjugate Acids & Bases
- Topic: What is a conjugate acid or base?
- Replies: 13
- Views: 1455
Re: What is a conjugate acid or base?
These can be confusing to me. I think of it like this:
A conjugate acid is the resulting formula when a base accepts a proton (H+), and a conjugate base is the species that results when an acid gives off a proton (H+).
A conjugate acid is the resulting formula when a base accepts a proton (H+), and a conjugate base is the species that results when an acid gives off a proton (H+).
- Mon Dec 07, 2020 2:15 pm
- Forum: Lewis Acids & Bases
- Topic: lewis vs bronsted
- Replies: 10
- Views: 410
Re: lewis vs bronsted
They are different definitions based on proton donating, accepting or electron donating, accepting.
Lewis acid accept electrons while lewis base donate electrons.
Bronsted acid gives proton, while bronsted base accepts protons.
Lewis acid accept electrons while lewis base donate electrons.
Bronsted acid gives proton, while bronsted base accepts protons.
- Sat Dec 05, 2020 1:49 pm
- Forum: Lewis Acids & Bases
- Topic: Classification of Lewis Acids and Bases
- Replies: 5
- Views: 263
Re: Classification of Lewis Acids and Bases
the main difference is that a lewis acid is an electron acceptor and a lewis base is an electron donor
- Wed Dec 02, 2020 5:35 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: 4 Ligands
- Replies: 3
- Views: 119
Re: 4 Ligands
I believe that it could be either, in this case.
- Wed Dec 02, 2020 5:34 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Sapling Number 3
- Replies: 8
- Views: 317
Re: Sapling Number 3
The coordination number is the number of bonds present. Both square planar and tetrahedral have four bonds.
- Wed Dec 02, 2020 5:33 pm
- Forum: Naming
- Topic: Oxidation State
- Replies: 16
- Views: 630
Re: Oxidation State
The oxidation state is the charge of an atom.
- Wed Dec 02, 2020 5:32 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: How to find Oxidation Numbers
- Replies: 4
- Views: 279
Re: How to find Oxidation Numbers
I think we are supposed to memorize these, however I am not sure if it will be given. I use this
https://sites.google.com/site/chempendix/ligands
https://sites.google.com/site/chempendix/ligands
- Wed Dec 02, 2020 5:31 pm
- Forum: Naming
- Topic: Sapling Q1
- Replies: 20
- Views: 898
Re: Sapling Q1
I had a similar problem. The cobalt has an oxidation state of +3 and not +2 because each Cl has a -1 charge and NH3 is a neutral compound. It is not +2, but is +3. Hopefully that helps
- Wed Dec 02, 2020 5:29 pm
- Forum: Naming
- Topic: Roman Numeral
- Replies: 3
- Views: 140
Re: Roman Numeral
I think you do it for the entire compound, not just what is in the brackets
- Wed Dec 02, 2020 5:19 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number
- Replies: 2
- Views: 158
Coordination Number
Classify each of the coordination compounds according to the coordination number.
How do you determine coordination number, and is this separate from oxidation number?
How do you determine coordination number, and is this separate from oxidation number?
Sapling 1
[Co(NH3)4Cl2]Cl :
Does anyone know how to arrange the ligands in alphabetical order here? Is it based on tetra and di or is it based on ammine and chloro?
Does anyone know how to arrange the ligands in alphabetical order here? Is it based on tetra and di or is it based on ammine and chloro?
- Thu Nov 26, 2020 2:20 pm
- Forum: Sigma & Pi Bonds
- Topic: Sigma and Pi Bonds
- Replies: 9
- Views: 820
Re: Sigma and Pi Bonds
sigma bonds are single bonds and pie bonds are double bonds
- Thu Nov 26, 2020 2:19 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling 16
- Replies: 6
- Views: 306
Sapling 16
How do we know what compounds form delocalized pie bonds, what does delocalized mean?
- Thu Nov 26, 2020 2:18 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Coordination Compounds
- Replies: 5
- Views: 169
Re: Coordination Compounds
H2O and OH2 is the same compound they are just written in a different order to show that the lone pairs on the O are what is bonding and forming the coordinate covalent bond with the transition metal cation.
- Thu Nov 26, 2020 2:15 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination number
- Replies: 9
- Views: 358
Re: Coordination number
Yes, you should count the double bond as two bonds in this case.
- Thu Nov 26, 2020 2:14 pm
- Forum: Hybridization
- Topic: e density
- Replies: 30
- Views: 1030
Re: e density
Yes. Both lone pairs and bonding pairs are regions of electron density.
- Thu Nov 26, 2020 2:13 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling 17
- Replies: 8
- Views: 507
Sapling 17
Draw the three possible structures of C3H4 . Be sure to include all atoms.
I am not sure how to draw the last structure for this?
I am not sure how to draw the last structure for this?
- Sat Nov 21, 2020 11:37 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: H20 Bent Structure
- Replies: 14
- Views: 621
Re: H20 Bent Structure
The reason that H20 is bent is because the oxygen has two lone pairs. These lone pairs cause repulsion of the two hydrogen atoms and pushes them downwards, thus causing a bent structure in the molecule
- Sat Nov 21, 2020 11:35 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle
- Replies: 9
- Views: 445
Re: Bond Angle
Yes, I think it will differ based on the exact atoms involved. This is because of the difference in the electronegativity of the atoms involved in bonding
- Sat Nov 21, 2020 11:34 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: sapling 8
- Replies: 3
- Views: 761
sapling 8
For each molecule, specify the polarity of the bonds and the overall polarity of the molecule.
How would we know if specific bonds are polar versus nonpolar versus the overall molecule being polar or nonpolar itself?
How would we know if specific bonds are polar versus nonpolar versus the overall molecule being polar or nonpolar itself?
- Sat Nov 21, 2020 11:32 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sampling 4
- Replies: 4
- Views: 237
Sampling 4
How many outer atoms and lone pairs are present in a molecule with a square pyramidal shape?
How are we supposed to determine this?
How are we supposed to determine this?
- Sat Nov 21, 2020 11:30 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: determining molecular shape
- Replies: 10
- Views: 527
Re: determining molecular shape
The reason for this is that there is a lone pair on the S atom in SO2. This then distorts the molecule and repels the atoms down into a bent molecular shape
- Thu Nov 12, 2020 11:59 am
- Forum: Lewis Structures
- Topic: Double Bonds
- Replies: 11
- Views: 272
Re: Double Bonds
You would want to place the double bond wherever it makes the formal charges closest to zero
- Thu Nov 12, 2020 11:58 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: 2.A.21
- Replies: 2
- Views: 179
2.A.21
Give the ground-state electron configuration and number of unpaired electrons expected for each of the following ions: (a)
Ca2+;(b) In+; (c) Te2−; (d) Ag+
I am not sure how to determine how many unpaired electrons there are
Ca2+;(b) In+; (c) Te2−; (d) Ag+
I am not sure how to determine how many unpaired electrons there are
- Thu Nov 12, 2020 11:57 am
- Forum: Electronegativity
- Topic: determining electronegativity
- Replies: 40
- Views: 5564
Re: determining electronegativity
One thing that helps me is using the acronym FONClBrISCH from F being most electronegative in the periodic table