Search found 101 matches

by Jessica Booth 2F
Thu Mar 12, 2020 4:56 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Just a reminder about pH and pKa!
Replies: 2
Views: 117

Re: Just a reminder about pH and pKa!

Comparing pKa/pKb with pH/pOH will be important to know how to do on the final - I think! See...pKa = -log(Ka), so the higher the pKa, the lower the Ka. Ka = \frac{[A-][H+]}{[HA]} Lower Ka means higher products - and lower H+ pH = -log(H+), which means the higher the pH, the lower the H+ Therefore,...
by Jessica Booth 2F
Thu Mar 12, 2020 4:53 pm
Forum: Balancing Redox Reactions
Topic: Oxidizing and Reducing
Replies: 5
Views: 47

Re: Oxidizing and Reducing

It depends on the situation that is being set up. If the cell is a galvanic cell then the half-reaction with the more negative potential will be oxidized and the half-reaction with the more positive potential will be reduced. If the set-up is for electrolysis, then the more negative potential will b...
by Jessica Booth 2F
Thu Mar 12, 2020 4:48 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Pre-Equilibrium Method
Replies: 4
Views: 71

Re: Pre-Equilibrium Method

The pre-equilibrium method is used to eliminate an intermediate in the rate law. In the pre-equilibrium method, the step before the slow step can be assumed to bottle-neck, creating a buildup of products. This allows products to go back to reactants and the reaction to be at equilibrium. From then y...
by Jessica Booth 2F
Thu Mar 12, 2020 4:43 pm
Forum: General Rate Laws
Topic: Fast and Slow Step Reactions
Replies: 5
Views: 95

Re: Fast and Slow Step Reactions

The slow step is the step with the highest activation energy. With regard to solving problems we use the slow step to determine if a given mechanism is correct for a reaction and to determine the order and rate law of a reaction.
by Jessica Booth 2F
Thu Mar 12, 2020 4:40 pm
Forum: General Rate Laws
Topic: 7A.9
Replies: 4
Views: 58

Re: 7A.9

You can tell because of the units of k, but you can also know that it is a first-order reaction because it tells you in the problem.
by Jessica Booth 2F
Thu Mar 12, 2020 4:38 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Textbook question 7.17
Replies: 4
Views: 73

Re: Textbook question 7.17

Since the slow step is the rate-determining step, if the catalyst doesn't accelerate the slow step, then the rate of the reaction won't change.
by Jessica Booth 2F
Wed Mar 11, 2020 12:16 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 interpretation
Replies: 2
Views: 86

Re: residual entropy interpretation

At T=0 K, the entropy that a molecule has is just due to the different microstates that the molecule could be in. At t=0 there are no other forms of entropy so you just have to calculate the entropy that arises from the molecule occupying different positions.
by Jessica Booth 2F
Wed Mar 11, 2020 12:10 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Activation energies for multi-step reactions
Replies: 2
Views: 55

Re: Activation energies for multi-step reactions

If there is a graph, you can look at the difference between the top of the bump to the starting energy level of the different fast steps to determine which fast step has a higher activation energy. In other words, the fast step with the largest "uphill section" will have the higher activat...
by Jessica Booth 2F
Wed Mar 11, 2020 12:05 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Arrhenius Equation A variable
Replies: 2
Views: 28

Re: Arrhenius Equation A variable

You can solve for k using this version of the Arrhenius equation: . To calculate k you need another k value for a different temperature and then you can subtract from and the lnA term will cancel.
by Jessica Booth 2F
Wed Mar 11, 2020 12:01 pm
Forum: General Rate Laws
Topic: intermediates
Replies: 12
Views: 69

Re: intermediates

Correct, they should be replaced using the equilibrium equation solved for the intermediate.
by Jessica Booth 2F
Mon Mar 09, 2020 11:58 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Rate determining step and Ea
Replies: 2
Views: 17

Re: Rate determining step and Ea

Yes, the rate-determining step will always have the highest activation energy because the step with the largest activation energy is the slowest step so it is the rate-determining step. To find the rate determining step when looking at the reaction profile, find the step with the largest difference ...
by Jessica Booth 2F
Mon Mar 09, 2020 11:06 pm
Forum: Second Order Reactions
Topic: 7.21 part H
Replies: 2
Views: 67

Re: 7.21 part H

Yes, it is because you have to account for the fact that the rate = A^{2} . From this equation, you can get the half-life equation which is t_{1/2}= \frac{1}{k[A]_{0}} . From this equation you can clearly see that with respect to [A], the half-life has an inverse relationship, so the plot won't be l...
by Jessica Booth 2F
Mon Mar 09, 2020 6:44 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: reaction profile
Replies: 2
Views: 48

reaction profile

How do you know if in a multistep reaction profile each starting energy for each step increases or decreases? For example in question 7.11, why doesn't the energy decrease each step instead of increasing?
by Jessica Booth 2F
Mon Mar 09, 2020 6:39 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Pre-Equilibrium Approach Constants
Replies: 1
Views: 21

Re: Pre-Equilibrium Approach Constants

the constant in the pre equilibrium approach is dependent on the coefficients of the species that you are using to determine the rate of. In class, this was the 2 NO. Also the constant depends on the rate constant of the slow step as well as the equilibrium expression that you solve for to replace t...
by Jessica Booth 2F
Sun Mar 08, 2020 9:00 pm
Forum: General Rate Laws
Topic: Arrhenius Equation
Replies: 3
Views: 37

Re: Arrhenius Equation

You can use the Arrhenius equation to find the activation energy as well as the rate constant at different temperatures.
by Jessica Booth 2F
Sun Mar 08, 2020 3:15 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: 7D.7
Replies: 1
Views: 23

Re: 7D.7

The equilibrium constant is the forward reaction constant over the reverse rate constant. For part b) you can think of it in terms of le chatlier's principle. Since the equilibrium constant is less than 1 you know that the reactant are favored and the reaction is endothermic. When you raise the temp...
by Jessica Booth 2F
Mon Mar 02, 2020 7:26 pm
Forum: Balancing Redox Reactions
Topic: Balancing half reactions in acidic conditions
Replies: 8
Views: 69

Balancing half reactions in acidic conditions

For a redox reaction in an acidic half-reaction, do we use H3O+ or just H+ to balance the hydrogens?
by Jessica Booth 2F
Sun Mar 01, 2020 9:48 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Galvanic and Voltaic Cells
Replies: 7
Views: 75

Re: Galvanic and Voltaic Cells

Galvanic and Voltaic cells are the same. They both get their energy from spontaneous reactions. The E of the cell will be positive and the is negative.
by Jessica Booth 2F
Sun Mar 01, 2020 9:44 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Reducing/oxidizing agent
Replies: 8
Views: 106

Re: Reducing/oxidizing agent

The reducing agent ends up becoming oxidized because it donates its electron to reduce another species. The oxidizing agent becomes reduced because it gains an electron from another species that becomes oxidized.
by Jessica Booth 2F
Sun Feb 23, 2020 6:24 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6L. 7 c
Replies: 2
Views: 49

6L. 7 c

Cd + 2Ni(OH)3 Cd(OH), why is there KOH on the anode side and Ni on the cathode side?
by Jessica Booth 2F
Sun Feb 23, 2020 5:47 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: cell diagrams
Replies: 1
Views: 21

cell diagrams

Is there a convention for which order you write the states in when there is an inert electrode. For example, for CL2 + H2 HCl, is there any order in which you have to write the H2 and H+ on the anode side?
by Jessica Booth 2F
Sun Feb 23, 2020 5:39 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6L.5 part b)
Replies: 2
Views: 33

6L.5 part b)

For , how can you tell that the are in the same solution and therefore need a inert electrode?
by Jessica Booth 2F
Sun Feb 23, 2020 2:41 pm
Forum: Balancing Redox Reactions
Topic: 6k. d
Replies: 1
Views: 20

6k. d

Will someone explain how to find the half-reactions for ?
by Jessica Booth 2F
Sun Feb 23, 2020 1:59 pm
Forum: Balancing Redox Reactions
Topic: 6K.5 a
Replies: 1
Views: 30

6K.5 a

How do you know that O3 is oxidized?
by Jessica Booth 2F
Sun Feb 23, 2020 1:41 pm
Forum: Balancing Redox Reactions
Topic: 6K.3
Replies: 1
Views: 29

6K.3

Will someone explain how to do part d? Cl2
by Jessica Booth 2F
Tue Feb 11, 2020 2:18 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: 4I.5
Replies: 1
Views: 28

Re: 4I.5

You can just keep the moles as grams in the calculations. However, you will need to convert to moles to find the heat to melt the ice as the is given in KJ/mol.
by Jessica Booth 2F
Tue Feb 11, 2020 2:14 pm
Forum: Phase Changes & Related Calculations
Topic: 4.C.13
Replies: 1
Views: 41

Re: 4.C.13

Because energy isn't lost you know that q1+q2=0 which means that q1=-q2. q1 is the heat required to first melt the ice and then increase its temperature to the final temp. So q_{1}=n\Delta H_{fus} +mC\Delta T . Also, q2 is the heat lost by the water when it is cooled down. So, q_{2}=mC\Delta T . Rem...
by Jessica Booth 2F
Tue Feb 11, 2020 2:10 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Constant R
Replies: 15
Views: 268

Re: Constant R

When do you use the constant R=8.314 vs 8.206x10^-2 and what are the units for each
The units are R = 8.314 J/(K mol) and 8.206x10^-2 L atm/(K mol). You use 8.314 whenever you are working with J and you use 8.206x10^-2 when using atm and L.
by Jessica Booth 2F
Tue Feb 11, 2020 2:07 pm
Forum: Phase Changes & Related Calculations
Topic: 4C.7
Replies: 1
Views: 31

Re: 4C.7

You should be able to use q=n. For part a) = 4.76 KJ/ .579 mol = 8.22 KJ/mol. Part b is the same except you need to convert the mass given into moles using the molar mass.
by Jessica Booth 2F
Tue Feb 11, 2020 2:04 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Test#1 Problem#6
Replies: 1
Views: 34

Re: Test#1 Problem#6

The correct kA value was 1.9 x10^-5.
by Jessica Booth 2F
Tue Feb 11, 2020 2:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Test#1 Problem#5
Replies: 1
Views: 33

Re: Test#1 Problem#5

After finding the Ka set up your ice table. You should get that the equilibrium conc. are [HClO2]= .15-x, [ClO2-]=x and [H3O+]=x. Then set up your equilibrium equation with the appropriate values. The Kc should = x^2/(.15-x) which also equals the Ka that is .012. Then solve the quadratic and you get...
by Jessica Booth 2F
Tue Feb 11, 2020 1:55 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: 4C.3
Replies: 1
Views: 38

Re: 4C.3

The correct answer for part a is 343 K and the correct answer for part b is 373K
by Jessica Booth 2F
Sun Feb 02, 2020 10:24 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: 4B.5
Replies: 3
Views: 43

Re: 4B.5

First, U=q+w. So you know that q= 5.50KJ. Then you know that there is a constant pressure so .
by Jessica Booth 2F
Sun Feb 02, 2020 10:21 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Constant volume vs constant pressure
Replies: 1
Views: 9

Re: Constant volume vs constant pressure

By definition, the enthalpy is the same as the heat transfer under constant pressure. Under conditions of constant volume, there is no work done, so the change in internal energy equals the enthalpy.
by Jessica Booth 2F
Sun Feb 02, 2020 10:18 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Adiabatic Wall
Replies: 3
Views: 32

Re: Adiabatic Wall

Adiabatic mean that , so a reaction can still absorb or release energy if work is done on the system or the system does work.
by Jessica Booth 2F
Sun Feb 02, 2020 10:16 pm
Forum: Calculating Work of Expansion
Topic: -PdeltaV
Replies: 2
Views: 15

Re: -PdeltaV

Because you are calculating the work done by the system, which is equal to the negative work done on the system. If a gas does work on its surrounding then the final volume is greater than the initial volume so in order to convey that the system lost energy the work must equal
by Jessica Booth 2F
Sun Feb 02, 2020 10:09 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Expansion Work
Replies: 2
Views: 34

Re: Expansion Work

Non-expansion work is work where the volume doesn't change. This could be muscle contractions or transmission of nerve impulses. expansion work is work that occurs when there is a change in volume. Work is for the most part independent of enthalpy except for when heat is added or taken away from a s...
by Jessica Booth 2F
Sun Feb 02, 2020 9:57 pm
Forum: Calculating Work of Expansion
Topic: Work vs. Enthalpy
Replies: 1
Views: 28

Re: Work vs. Enthalpy

Yes, there are scenarios where a closed reaction would do work on the system but still have positive enthalpy because the sign of the enthalpy doesn't indicate anything about the work. It is possible for a system to lose heat, having a negative q but do work on the surroundings by expanding. Exother...
by Jessica Booth 2F
Sun Jan 26, 2020 10:36 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Standard Reaction Enthalpies
Replies: 2
Views: 21

Re: Standard Reaction Enthalpies

It does not matter if the products and reactants are in different states. However, you do have to differentiate between the states because there can be different enthalpies of formation for different phases of the same molecule.
by Jessica Booth 2F
Sun Jan 26, 2020 3:15 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: bond v. standard
Replies: 5
Views: 42

Re: bond v. standard

Bond enthalpies are the energy required to break a bond, while standard enthalpies of formation are the reaction enthalpies for the formation of 1 mol of a substance from its elements in their most table form.
by Jessica Booth 2F
Sun Jan 26, 2020 1:07 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Method 3 - Enthalpy
Replies: 2
Views: 16

Re: Method 3 - Enthalpy

Basically you take the sum of the enthalpies of formation of the products and subtract the sum of enthalpies of formation of the reactants.
by Jessica Booth 2F
Mon Jan 20, 2020 2:27 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6E.1
Replies: 2
Views: 25

Re: 6E.1

The concentration of H30+ is initially .15 M for the second protonation because .15 M H2SO4 produces .15 M H3O+ so when the second protonation starts there is already .15M H3O+ in solution from the first protonation.
by Jessica Booth 2F
Mon Jan 20, 2020 2:22 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Percent ionization
Replies: 2
Views: 21

Re: Percent ionization

Partially. The percent ionization is the amount of ionized product divided by the amount of reactant. So it tells us the ratio of ionized product to unionized reactant.
by Jessica Booth 2F
Sun Jan 19, 2020 1:44 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Homework 6E.3
Replies: 3
Views: 36

Homework 6E.3

The question is: Calculate the pH of each of the following solutions of diprotic acids at 25 ignoring second deprotonations only when the approximation is justified. How do you tell if ignoring the second deprotonation is justified?
by Jessica Booth 2F
Mon Jan 13, 2020 7:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework 5.39
Replies: 1
Views: 20

Homework 5.39

What information were we supposed to find in table 5E. 2? My book didn't have a table 5E. 2.
by Jessica Booth 2F
Mon Jan 13, 2020 7:36 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework 5.35
Replies: 3
Views: 47

Homework 5.35

The following plot shows how the partial pressures of reactant and products vary with time for the decomposition of compound A into compounds B and C. All three compounds are gases. Use this plot to do the following: write the balanced chemical equation for the reaction. b) calculate the equilibrium...
by Jessica Booth 2F
Mon Jan 13, 2020 7:33 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework 5l. 29
Replies: 2
Views: 26

Homework 5l. 29

At 25 K = 3.2 x for the reaction 2HCl H2 + Cl2. If a reaction vessel of volumme 1.0L is filled with HCl at .22 bar, what are the equilibrium partial pressures of HCl, H2, and Cl2.
by Jessica Booth 2F
Sun Jan 12, 2020 11:39 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: pressure change
Replies: 4
Views: 32

Re: pressure change

The general rule for change in pressure is that if the pressure has increased the side of the reaction with fewer moles is favored. This, however, only applies if the pressure is changed by changing the volume because then the concentrations change.
by Jessica Booth 2F
Sun Jan 12, 2020 11:37 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: appliction of principle
Replies: 5
Views: 52

Re: appliction of principle

It applies to changes in concentration, pressure, or temperature.
by Jessica Booth 2F
Sun Jan 12, 2020 11:36 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE
Replies: 5
Views: 76

Re: ICE

The ice tables are mainly used when we only know the initial concentration(s) and the equilibrium constant. Basically, we use ice tables when we are unable to just use the equilibrium concentrations and equilibrium constant to find the other equilibrium concentrations.
by Jessica Booth 2F
Fri Dec 06, 2019 10:55 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: pKa and Ka
Replies: 9
Views: 178

Re: pKa and Ka

Ka is the acid dissociation constant and is equal to [H+][A-]/[HA]. The pKa is the -log of the Ka. The Ka and pKa tell you the strength of a weak acid. The larger the Ka and the smaller the pKa the stronger the acid.
by Jessica Booth 2F
Fri Dec 06, 2019 10:52 am
Forum: Bronsted Acids & Bases
Topic: Strong Acids and Bases
Replies: 2
Views: 38

Re: Strong Acids and Bases

I'm not sure if these are all the ones we need to know but here are some: strong acids: HCl, HI, HBr, H2SO4, HNO3, HClO4. Strong bases: LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2.
by Jessica Booth 2F
Fri Dec 06, 2019 10:48 am
Forum: Dipole Moments
Topic: Dipole Moments Cancel in Tetrahedral?
Replies: 5
Views: 155

Re: Dipole Moments Cancel in Tetrahedral?

No, they would not cancel. The only way to have a nonpolar tetrahedral molecule is if all the atoms attached to the central atom are the same.
by Jessica Booth 2F
Fri Dec 06, 2019 10:43 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: How to tell the strength of a base
Replies: 2
Views: 37

How to tell the strength of a base

Are the guidelines for determining how strong a base is the same as the guidelines for relative acidity?
by Jessica Booth 2F
Fri Dec 06, 2019 10:41 am
Forum: Hybridization
Topic: pi bonds
Replies: 1
Views: 34

Re: pi bonds

Pi bonds are formed using unhybridized orbitals. If a bond is using sp2 orbitals then the pi bonds are formed using p orbitals.
by Jessica Booth 2F
Sun Dec 01, 2019 6:55 pm
Forum: Conjugate Acids & Bases
Topic: Conjugate acids/bases
Replies: 1
Views: 30

Re: Conjugate acids/bases

'm still not exactly sure what a conjugate acid is. If a molecule gives off a proton in a reaction, in the reverse reaction is it then the conjugate base since it receives a proton? A conjugate acid is a compound that starts out as a base and then gains an H+. If a molecule gives off an H+ in a reac...
by Jessica Booth 2F
Sun Dec 01, 2019 6:48 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH
Replies: 4
Views: 37

Re: Calculating pH

To calculate the pH of a solution take the -log of the concentration of H3O+ ions.
by Jessica Booth 2F
Sun Dec 01, 2019 6:46 pm
Forum: Amphoteric Compounds
Topic: 6A.11
Replies: 1
Views: 34

Re: 6A.11

Amphiprotic means that the compound can act as both an acid and a base by either accepting or donating an H+. The easiest way to answer this question is to write the chemical reaction between the given compound and H2O. Then show the products when the compound is acting as an acid and as a base. For...
by Jessica Booth 2F
Sat Nov 30, 2019 5:12 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Homework 6C.21
Replies: 1
Views: 48

Homework 6C.21

Why is HCOOH a stronger acid than CH3COOH? I would assume that CH3COOH would be stronger because of the larger delocalization of charge caused by the CH3 group?
by Jessica Booth 2F
Sat Nov 30, 2019 5:02 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Homework 6c.19
Replies: 1
Views: 46

Homework 6c.19

part c asks whether HBrO2 or HClO2 is a stronger acid. the H-Br bond is longer and therefore weaker than the H-Cl bond, so why is HClO2 the stronger acid?
by Jessica Booth 2F
Sun Nov 24, 2019 7:02 pm
Forum: Lewis Acids & Bases
Topic: HCl vs HF
Replies: 19
Views: 222

Re: HCl vs HF

F is more electronegative than Cl so it is less likely to give off the H+ ion. This means that HCl can disassociate easier, making it the stronger acid.
by Jessica Booth 2F
Sun Nov 24, 2019 6:58 pm
Forum: Hybridization
Topic: Hybridization
Replies: 1
Views: 37

Re: Hybridization

You can count the number of regions of high electron density (a bond or lone pair) and then from there assign it a hybridization with the sample number of orbitals as electron densities. For example if the molecule had 3 areas of high electron density then you would choose a hybridization that has 3...
by Jessica Booth 2F
Sun Nov 24, 2019 6:54 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: 9C.9
Replies: 1
Views: 23

Re: 9C.9

To find the coordination number count the number of bonds that the transition metal forms. For a) the Ni is bonded to 4 Cl so the coordination number is 4. Remember that en is bidentate and edta is hexadentate.
by Jessica Booth 2F
Sun Nov 24, 2019 6:52 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: [PtCl2(en)2] 2+
Replies: 3
Views: 26

Re: [PtCl2(en)2] 2+

It has a coordination number of 6 because it forms a bond with each of the Cl's and then each of the en is bidentate so each en bonds twice to the Pt and since there's 2 of them that's 4 bonds. Then the total number of bonds the Pt has is 6.
by Jessica Booth 2F
Sun Nov 24, 2019 6:49 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelating Ligand
Replies: 1
Views: 19

Re: Chelating Ligand

Cheating ligand form a ring of atoms that include the central metal atom. Chelating ligands have to be multidentate the chelate.
by Jessica Booth 2F
Sun Nov 17, 2019 8:46 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Drawing the Lewis Structure of N20 (2E.13d)
Replies: 5
Views: 55

Re: Drawing the Lewis Structure of N20 (2E.13d)

First, you count up all the valence electrons, 2(5) + 6= 16. Then you put the less electronegative atom in the middle, which is N. Then you arrange the O and other N symmetrically around the central O. Then you put the 16 electrons around the atoms. You find out that with just single bonds, not all ...
by Jessica Booth 2F
Sun Nov 17, 2019 8:27 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Terminal Atom
Replies: 2
Views: 33

Re: Terminal Atom

Terminal atoms are just the atoms surrounding the central atom in a Lewis Structure. For example, Cl is a terminal atom in CCl4.
by Jessica Booth 2F
Sun Nov 17, 2019 8:26 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR
Replies: 7
Views: 74

Re: VSEPR

Correct. We will not be asked to draw them but we will need to name the shapes.
by Jessica Booth 2F
Sun Nov 17, 2019 8:25 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular shape
Replies: 3
Views: 26

Re: Molecular shape

Yes, seesaw and sawhorse both have the VSEPR model AX4E
by Jessica Booth 2F
Thu Nov 14, 2019 1:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Homework 2E.11
Replies: 3
Views: 40

Homework 2E.11

Use Lewis Structures and the VSEPR model to give the VSEPR formula for each of the following species and predict its shape:
a)sulfur tetrachloride
b)iodine trichloride
c) IF4-
d)xenon trioxide
What is the VSEPR formula for each part and how do you find it?
by Jessica Booth 2F
Sun Nov 10, 2019 8:48 pm
Forum: Dipole Moments
Topic: 3F.3 c
Replies: 1
Views: 26

Re: 3F.3 c

It experiences a dipole moment because the Cl's and H's are next to each other and so there is a dipole moment pointing from the H to the C and from the C to the Cl. So, therefore, the dipole moments add in both directions so the dipole moment points from the H to the Cl.
by Jessica Booth 2F
Sun Nov 10, 2019 8:33 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: Polarizability
Replies: 3
Views: 26

Re: Polarizability

The bigger the atom, the more polarizable it will be because the outer electrons feel the pull of the nucleus less so they can be more distorted. The number of electrons is indicative of the size.
by Jessica Booth 2F
Sun Nov 10, 2019 8:04 pm
Forum: Lewis Structures
Topic: CH2Cl2 structure
Replies: 1
Views: 54

CH2Cl2 structure

How do you determine that in the lewis structure of CH2Cl2 the Cl's are next to each other and the H's are next to each other instead of the Cl's and H's being across from each other?
by Jessica Booth 2F
Sun Nov 03, 2019 12:59 pm
Forum: Electronegativity
Topic: Electron Affinity
Replies: 3
Views: 47

Re: Electron Affinity

Electron affinity is the energy released when an electron is added to a gas-phase atom. Electronegativity is the electron-pulling power of an atom when it is part of a molecule. Electronegativity is the average of the ionization energy and electron affinity of an element.
by Jessica Booth 2F
Sun Nov 03, 2019 12:53 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Degenerate orbitals?
Replies: 1
Views: 45

Re: Degenerate orbitals?

Yes, all 3 of the 2p orbitals and all 5 of the 3d orbitals are degenerate because they are at the same energy level.
by Jessica Booth 2F
Sun Nov 03, 2019 12:50 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: general question
Replies: 2
Views: 56

Re: general question

Polarizability is how much an electron cloud of an atom or ion can undergo a large distortion. Atoms or ions with a large distortion are highly polarizable. The larger the atom the more polarizable it is.
by Jessica Booth 2F
Sun Nov 03, 2019 12:46 pm
Forum: Bond Lengths & Energies
Topic: 2D.19
Replies: 1
Views: 40

Re: 2D.19

"Use the covalent radii in Fig. 2D.11 to calculate the bond lengths in the following molecules. Account for the trends in your calculated values: (a) CF 4; (b) SiF 4; (c) SnF 4" In order to find the bond length of covalent bonds you need to add together the 2 covalent radii for the element...
by Jessica Booth 2F
Mon Oct 28, 2019 2:34 pm
Forum: Ionic & Covalent Bonds
Topic: Homework 2B.11
Replies: 1
Views: 20

Homework 2B.11

Draw the complete Lewis structure for each of the following compounds:
c) H2C(NH2)COOH
How do you determine the arrangement of the atoms and which atoms are bonded to another?
by Jessica Booth 2F
Sun Oct 27, 2019 10:36 pm
Forum: Ionic & Covalent Bonds
Topic: 2A. 9
Replies: 2
Views: 37

Re: 2A. 9

This is the question: Which M2+ ions (where M is a metal) are predicted to have the following ground-state electron configurations: (a) [Ar]3d7; (b) [Ar]3d6; (c) [Kr]4d4; (d) [Kr]4d3? a) Because there is a 2+ charge we need to add 2 electrons to the given number of valence electrons, which in this c...
by Jessica Booth 2F
Sun Oct 27, 2019 10:25 pm
Forum: Ionic & Covalent Bonds
Topic: Valence Electrons
Replies: 3
Views: 37

Re: Valence Electrons

You start from the left side of the periodic table and count across a period until you reach the element you're trying to find. The count is the number of valence electrons. If you're trying to find the number of valence electrons for a cation then you find the number of valence electrons and subtra...
by Jessica Booth 2F
Sun Oct 27, 2019 10:19 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Elements having octets
Replies: 4
Views: 70

Re: Elements having octets

C,N,O,F always form an octect and anything with an atomic number above F has a d-shell, so they can form expanded octects.
by Jessica Booth 2F
Sun Oct 27, 2019 10:16 pm
Forum: Trends in The Periodic Table
Topic: Cations vs Parent atoms
Replies: 4
Views: 49

Re: Cations vs Parent atoms

Cations are smaller than their parent atoms because there is less electron-electron repulsion but there is still the same number of protons so the electrons are closer to the nucleus.
by Jessica Booth 2F
Sun Oct 27, 2019 10:13 pm
Forum: Ionic & Covalent Bonds
Topic: 2A. 1 Question
Replies: 2
Views: 35

Re: 2A. 1 Question

Sb and Mn have electrons in the d-shell so those electrons are counted as valence electrons because they are in the outermost shell.
by Jessica Booth 2F
Sun Oct 20, 2019 7:46 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 1E.17 Ion formation
Replies: 1
Views: 25

Re: 1E.17 Ion formation

Electrons are removed from the highest energy orbital and the energies of orbitals go s<p<d<f.
by Jessica Booth 2F
Sun Oct 20, 2019 7:42 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Problem 1E.25
Replies: 2
Views: 34

Re: Problem 1E.25

1E.25 Give the notation for the valence-shell configuration
(including the outermost d-electrons) of (a) the alkali metals;
(b) Group 15 elements; (c) Group 5 transition metals; (d) the
“coinage” metals (Cu, Ag, Au).
a) ns^1
b) ns^2 np^3
c) omit
d) (n-1)d^10 ns^1
by Jessica Booth 2F
Sun Oct 20, 2019 7:34 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Problem 1E.5
Replies: 2
Views: 40

Re: Problem 1E.5

Electrons in an s-orbital are more effective at shielding other electrons because the penetration levels go ns > np > nd > nf. The higher the penetration the more effective an electron is at shielding others. The s-orbital is closest to the nucleus so it is the most effective at shielding other elec...
by Jessica Booth 2F
Sun Oct 20, 2019 7:28 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: electron configuration exceptions
Replies: 3
Views: 39

Re: electron configuration exceptions

what were the electron configuration exceptions, and does anyone know why they are exceptions? additionally, other than asking what the exceptions are on an exam, what kind of questions would test this knowledge of exceptions? The exceptions that we need to know are Cr whose electron configuration i...
by Jessica Booth 2F
Sun Oct 20, 2019 7:21 pm
Forum: Quantum Numbers and The H-Atom
Topic: Orbital orders
Replies: 2
Views: 58

Re: Orbital orders

The s < p < d < f is referring to the energy levels of different subshells. They can all exist at the same time for example boron has electrons in the 2s and 2p orbitals. The only limitation is if the atom doesn't have enough electrons to need to fill the p, d, or f levels. For example, magnesium do...
by Jessica Booth 2F
Sun Oct 20, 2019 7:16 pm
Forum: Photoelectric Effect
Topic: 1B.15
Replies: 2
Views: 65

Re: 1B.15

keV is kilo-electron volts, which is a unit for energy. The conversion from kilo- electron volts to electron volts is (1000 eV/keV) and then the conversion from eV to J is J/ 1eV.
by Jessica Booth 2F
Sun Oct 13, 2019 1:20 pm
Forum: Properties of Light
Topic: 1A3
Replies: 5
Views: 65

Re: 1A3

The speed in the question is referring to the speed of light which is always
by Jessica Booth 2F
Sat Oct 12, 2019 6:09 pm
Forum: Properties of Light
Topic: Homework 1A 15
Replies: 2
Views: 44

Homework 1A 15

Will someone explain how to find the final and initial energy levels of an electron during the emission of energy that leads to a spectral line observed at 102.6 nm in the ultraviolet spectrum of atomic hydrogen using the equation from class?
by Jessica Booth 2F
Sat Oct 12, 2019 5:54 pm
Forum: Properties of Light
Topic: ∝ notation
Replies: 2
Views: 55

Re: ∝ notation

Yes ,if instead b had said the wavelength increases it would have been correct because c= so wavelength and frequency have an inverse relationship so when one increased the other has to decrease.
by Jessica Booth 2F
Sat Oct 12, 2019 5:50 pm
Forum: Properties of Light
Topic: Homework 1A3
Replies: 2
Views: 55

Homework 1A3

Why is the speed of the radiation constant when the frequency of EM radiation decreases?
by Jessica Booth 2F
Fri Oct 04, 2019 11:13 am
Forum: Molarity, Solutions, Dilutions
Topic: Homework Question G11
Replies: 2
Views: 78

Re: Homework Question G11

Using the fact that n = MV, by rearranging the equation you get V = n/M. 4.50 mmol = 4.5 x 10^-3 m so V = (4.5 x 10^-3 m)/ (.278 M) = 16.2 mL
by Jessica Booth 2F
Fri Oct 04, 2019 10:46 am
Forum: SI Units, Unit Conversions
Topic: What is a t
Replies: 2
Views: 83

What is a t

In homework L35 it asks you to use a mass of 2.50 t. What is the conversion from t to grams?
by Jessica Booth 2F
Fri Oct 04, 2019 10:45 am
Forum: SI Units, Unit Conversions
Topic: Homework: L35
Replies: 2
Views: 78

Re: Homework: L35

Also the last equation that you balanced isn't balanced because the textbook has an error and the last equation should be Fe3Br8 + Na2CO3 forms NaBr + CO2 + Fe3O4.
by Jessica Booth 2F
Fri Oct 04, 2019 10:42 am
Forum: Balancing Chemical Reactions
Topic: Homework L35
Replies: 1
Views: 46

Re: Homework L35

Nevermind, the textbook has an error on problem L35. The last equation should be Fe3Br8 + Na2CO3 forms NaBr + CO2 + Fe3O4.
by Jessica Booth 2F
Fri Oct 04, 2019 10:32 am
Forum: Balancing Chemical Reactions
Topic: Homework L35
Replies: 1
Views: 46

Homework L35

How do you balance this equation?
FeBr2 + Na2CO3 goes to form NaBr + CO2 + Fe3O4

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