Search found 68 matches

by 804994652
Sun Mar 17, 2019 9:25 am
Forum: *Alkanes
Topic: Final
Replies: 13
Views: 999

Re: Final

So we would want to remember the 6 functional groups?
by 804994652
Sat Mar 16, 2019 9:31 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Cv or Cp
Replies: 3
Views: 100

Cv or Cp

How do you know whether to use Cv=(3/2)*R or Cp=(5/2)*R?
by 804994652
Wed Mar 13, 2019 12:21 am
Forum: Second Order Reactions
Topic: 2nd order rates
Replies: 6
Views: 140

2nd order rates

Just to clarify:
If a 2nd order rate looked like rate = k [OH-] [H3Br]
the rate is second order for the reaction
but the rate is first order for each reactant?
by 804994652
Tue Mar 12, 2019 9:56 pm
Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
Topic: Electrolysis
Replies: 2
Views: 217

Electrolysis

I'm confused as to what we need to know for electrolysis for the final?
by 804994652
Sun Mar 10, 2019 11:24 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6L.3
Replies: 1
Views: 26

6L.3

In the 7th edition, 6L #3 part a it asks for the half reactions for problems like Ni(s) | Ni2+ (aq) || Ag+ (aq) | Ag (s) are the half reactions: Ag+ (aq) + e- --> Ag (s) E(cathode) = +0.80 V Ni2+ (aq) + 2e- --> Ni (s) E (anode) = -0.23 V OR ARE THE HALF REACTIONS (with the reversed anode half reacti...
by 804994652
Sun Mar 10, 2019 11:03 pm
Forum: Balancing Redox Reactions
Topic: 6K.3 part d
Replies: 2
Views: 38

Re: 6K.3 part d

So you would set it up the half reactions like: Cl2 (g) --> HClO (aq) + Cl2 (g)
Cl2 + 2 H2O --> 2 HCLO(g) + 2H+
Cl2 --> Cl2 (g)??
by 804994652
Sun Mar 10, 2019 11:01 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Enot
Replies: 2
Views: 74

Re: Enot

E not is made up of state functions so therefore it is a state function
by 804994652
Sun Mar 10, 2019 7:46 pm
Forum: Balancing Redox Reactions
Topic: 6K.3 part d
Replies: 2
Views: 38

6K.3 part d

In the 7th edition, 6K #3 asks that you balance the following redox rxn in an acidic solution and find the oxidizing/reducing agent. Part d had the equation) Cl2 (g) --> HClO (aq) + Cl2 (g) The answer is H2O (l) + Cl2 (g) --> HOCl (aq) + H+ (aq) + Cl- (aq) where Cl2 is both the oxidizing and reducin...
by 804994652
Sun Mar 03, 2019 11:28 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Element's potentials
Replies: 5
Views: 110

Re: Element's potentials

Should we be using the periodic table reference in the text or the list of potentials in the textbook?
by 804994652
Sun Mar 03, 2019 11:24 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Pt(s)
Replies: 10
Views: 133

Re: Pt(s)

You need something for it to attach to (a solid). I'm not exactly sure why it has to be Pt though
by 804994652
Sun Mar 03, 2019 11:23 pm
Forum: Balancing Redox Reactions
Topic: OH-
Replies: 5
Views: 104

OH-

how do you know when you need to add OH-
by 804994652
Sun Feb 24, 2019 11:34 pm
Forum: *Free Energy of Activation vs Activation Energy
Topic: Spontaneous reactions
Replies: 7
Views: 750

Re: Spontaneous reactions

You just want to make sure delta G is negative. So if the equation (ΔG=ΔH−TΔS) is manipulated in a way in which delta G is negative, it is spontaneous.
by 804994652
Sun Feb 24, 2019 11:31 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Test 2
Replies: 9
Views: 153

Re: Test 2

Are the other parts of thermodynamics section going to be included?
by 804994652
Sun Feb 24, 2019 11:30 pm
Forum: Balancing Redox Reactions
Topic: Work done
Replies: 2
Views: 49

Re: Work done

I thought when delta E was positive, system was gaining Energy?
by 804994652
Sun Feb 17, 2019 11:10 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Ideal Gas C
Replies: 5
Views: 176

Re: Ideal Gas C

I think it has something to do with the fact that Cp= Cv+R. Since Cv=3/2 R that would mean Cp= 3/2R + R = 5/2R
by 804994652
Sun Feb 17, 2019 11:07 pm
Forum: Ideal Gases
Topic: Calculating Pressure of a Gas Mixture Using PV=nRT
Replies: 3
Views: 135

Re: Calculating Pressure of a Gas Mixture Using PV=nRT

You can also solve for each one individually and then add them together
by 804994652
Tue Feb 12, 2019 7:45 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Std Enthalpy of Formations
Replies: 1
Views: 33

Std Enthalpy of Formations

Why is it that molecules like O2 and N2 not included when trying to figure out enthalpy of a reaction...?
by 804994652
Sun Feb 10, 2019 11:15 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: 4C.3
Replies: 1
Views: 30

4C.3

In the 7th Ed. section 4c. #3 it asks that you find the final T and change in enthalphy when a) @ constant pressure and b) @ constant volume
I know when there is constant pressure the change in enthalpy, delta H= q
Is it the same for when there is constant volume?
delta H=q???
by 804994652
Sat Feb 09, 2019 11:52 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 4A.13
Replies: 2
Views: 56

Re: 4A.13

Thank you!
Do you think that this explanation makes sense: Since the reaction released the 3.5 kj, the calorimeter is getting the 3.50kj of work done on it.. So when work is done on the system (calorimeter), it is (+)?
by 804994652
Sat Feb 09, 2019 10:00 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Gas constant, R
Replies: 3
Views: 63

Gas constant, R

How do you know which Gas constant, R to use 8.206 e-2 L atm k-1 mol-1 or 8.314 e-2 J k-1 mol-1?
by 804994652
Sat Feb 09, 2019 7:35 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 4A.13
Replies: 2
Views: 56

4A.13

In the 7th Ed. Section 4A Q13, the problem states "a constant volume calorimeter was calibrated by carrying out a rxn known to release 3.5 kJ if heat in 0.2 L of sol. in the calorimeter (q=-3.50kJ). When calculating C, the solutions manual changed the q from -3.50 kj to + 3.50 kj...why?
by 804994652
Sun Feb 03, 2019 11:22 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Heat VS. Energy
Replies: 5
Views: 96

Re: Heat VS. Energy

heat=energy and enthalpy is the transfer of heat/energy
by 804994652
Sun Feb 03, 2019 11:19 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Closed Systems
Replies: 6
Views: 69

Re: Closed Systems

What are some examples of both?
by 804994652
Mon Jan 28, 2019 8:47 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: K versus C*
Replies: 2
Views: 46

K versus C*

In class, Lavelle used Kelvin and Celsius interchangeably when describing specific heat. How is it that that the heat required to raise the temperature of some ethanol is 49 kJ/C* or kJ/K?
by 804994652
Sun Jan 27, 2019 7:48 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J.11 (b) 7th edition
Replies: 2
Views: 60

Re: 5J.11 (b) 7th edition

It can be helpful to view heat as a reactant since it is endothermic according to the explanation in the response above.
by 804994652
Tue Jan 22, 2019 5:00 pm
Forum: Ideal Gases
Topic: ICE table
Replies: 5
Views: 163

Re: ICE table

If they give you barr and a volume that is not 1.0L is that volume significant? As in, do we need to change the barr by dividing it by volume?
by 804994652
Mon Jan 21, 2019 10:41 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Stability
Replies: 3
Views: 47

Stability

What is the correlation between how small/big the equilibrium constant is in comparison to the stability?
by 804994652
Sat Jan 19, 2019 1:15 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: temperature
Replies: 2
Views: 73

Re: temperature

In what cases would we need to manipulate the equation then when there is a temperature change?
by 804994652
Sat Jan 19, 2019 1:13 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Explaining pressure increase in terms of concentration
Replies: 2
Views: 63

Re: Explaining pressure increase in terms of concentration

increasing pressure favors the side with fewer moles of gas, in this case it would be reactants
by 804994652
Fri Jan 18, 2019 3:25 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Equations with Salt
Replies: 2
Views: 47

Re: Equations with Salt

The rule of thumb is that salts completely dissassociate
by 804994652
Mon Jan 14, 2019 11:28 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Volume and Pressure
Replies: 2
Views: 38

Volume and Pressure

I understand that volume and pressure are inversely related, I'm still a little confused about how this correlates with favoring the side with more moles?
by 804994652
Mon Jan 14, 2019 11:17 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Converting Kc to Kp
Replies: 3
Views: 132

Re: Converting Kc to Kp

I think we've learned how to find Kc and Kp (the way to do it for each is essentially the same) however we have not learned how to convert between the two. We know how to take pressure to concentration.
by 804994652
Mon Jan 14, 2019 7:16 pm
Forum: Ideal Gases
Topic: Kc and Kp
Replies: 6
Views: 100

Re: Kc and Kp

Does 'K' most often refer to Kp or Kc?
by 804994652
Sun Dec 09, 2018 7:49 pm
Forum: Lewis Acids & Bases
Topic: Na+
Replies: 3
Views: 212

Re: Na+

There's a table in the textbook that shows that Na+ is a neutral in acid/base rxns so in the net equation it is not included.
by 804994652
Sat Dec 08, 2018 1:12 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Equilibria for weak acids/bases
Replies: 1
Views: 57

Equilibria for weak acids/bases

For weak acids/bases since they do not deionize completely, the arrow should be that of constant equilibria between reactants and products (one arrow for forward rxn and one arrow for backward rxn). However in the textbook (7th ed) in Fundamentals J question 17 a-d that asks for the chem eqn for the...
by 804994652
Fri Dec 07, 2018 10:25 pm
Forum: Hybridization
Topic: Composition of a sigma bond with Hydrogen
Replies: 1
Views: 46

Composition of a sigma bond with Hydrogen

How would the composition of a sigma bond with a hydrogen be written. i.e. a single bond between H and C
Would it look something like sigma (C 2sp^3 , H s)?
by 804994652
Tue Dec 04, 2018 12:18 am
Forum: Naming
Topic: Roman Numerals
Replies: 2
Views: 43

Re: Roman Numerals

so not necessary when we name them?
by 804994652
Mon Dec 03, 2018 11:45 pm
Forum: Naming
Topic: Roman Numerals
Replies: 2
Views: 43

Roman Numerals

When naming complex ions, should we include the roman numerals indicating the charge of the acid. The solutions manual did not include roman numerals.
by 804994652
Mon Dec 03, 2018 3:08 pm
Forum: Administrative Questions and Class Announcements
Topic: Chemistry Community Submissions
Replies: 2
Views: 82

Re: Chemistry Community Submissions

Thank you! My name is not online publicly, is that still okay?
by 804994652
Mon Dec 03, 2018 2:51 pm
Forum: Administrative Questions and Class Announcements
Topic: Chemistry Community Submissions
Replies: 2
Views: 82

Chemistry Community Submissions

Is there some place we can check to make sure our chemistry community submissions have been going through every week?
by 804994652
Sun Dec 02, 2018 6:35 pm
Forum: Bronsted Acids & Bases
Topic: Calculations Involving Strong Acid (or Base)
Replies: 3
Views: 50

Re: Calculations Involving Strong Acid (or Base)

Are you referring to the problems that take the pH and do calculations with that using log?
by 804994652
Sun Dec 02, 2018 6:30 pm
Forum: Naming
Topic: Common ions
Replies: 1
Views: 32

Common ions

Are there common ions we should know when it comes to naming? and what are they?
by 804994652
Sun Dec 02, 2018 6:29 pm
Forum: Naming
Topic: Naming
Replies: 2
Views: 47

Naming

What is the order when it comes to naming?
by 804994652
Sun Nov 25, 2018 10:30 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7348
Views: 900291

Re: Post All Chemistry Jokes Here

What is the gender of Iron Man?
Fe Male
by 804994652
Sun Nov 25, 2018 10:17 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7348
Views: 900291

Re: Post All Chemistry Jokes Here

once i told a chemistry joke...there was no reaction.
by 804994652
Sun Nov 25, 2018 10:13 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7348
Views: 900291

Re: Post All Chemistry Jokes Here

If Avogadro calls tell him to leave his number
by 804994652
Sun Nov 25, 2018 10:07 pm
Forum: Hybridization
Topic: Double Bonds
Replies: 4
Views: 79

Re: Double Bonds

So if double bonds are both sigma and pi bonds, is it in hybridized orbital or between pi orbitals?
by 804994652
Sun Nov 25, 2018 9:54 pm
Forum: Hybridization
Topic: promoted hybridization
Replies: 4
Views: 86

Re: promoted hybridization

It is simply when an electron goes from a lower to higher energy level. Energy is released (negative).
by 804994652
Sun Nov 25, 2018 9:53 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Nodal Planes
Replies: 3
Views: 56

Nodal Planes

What exactly is a nodal plane?
by 804994652
Sun Nov 11, 2018 9:29 pm
Forum: Octet Exceptions
Topic: learning octet excptions
Replies: 4
Views: 88

Re: learning octet excptions

I would say the elements where the octet rule is strictly enforced is rows 1 & 2 (other than H/He) since rows 3 on have access to d orbital like the above response mentioned.
by 804994652
Sun Nov 11, 2018 9:24 pm
Forum: Electronegativity
Topic: Electron Affinity
Replies: 3
Views: 93

Re: Electron Affinity

The more stable ion is K+ because it has a full shell, thus it is less likely to gain an electron.
by 804994652
Sun Nov 11, 2018 9:22 pm
Forum: Resonance Structures
Topic: Drawing resonance structures
Replies: 5
Views: 222

Re: Drawing resonance structures

When they ask for the lewis structures, does that refer to all lowest energy resonance structures?
by 804994652
Sun Nov 04, 2018 10:00 am
Forum: Lewis Structures
Topic: Drawing Lewis Structures
Replies: 14
Views: 300

Re: Drawing Lewis Structures

I'm still confused about the arrangement about the atoms. For examples TB (7th ed) 2C.3c says to draw the lewis structure of HClO3 and I arranged the atoms of oxygen and hydrogen around Cl. The solution manual put the H connected to the Oxygen instead. How would I have known to do this?
by 804994652
Sun Nov 04, 2018 9:50 am
Forum: Lewis Structures
Topic: Common Ions-Midterm [ENDORSED]
Replies: 1
Views: 60

Common Ions-Midterm [ENDORSED]

What are the common ions we should know as some of the homework questions do not give us formulas but the name i.e. Draw the Lewish Structure for Chloric Acid
by 804994652
Sat Nov 03, 2018 10:21 pm
Forum: Lewis Structures
Topic: Complete Lewis Structures
Replies: 1
Views: 33

Complete Lewis Structures

Does anyone know the difference between lewis structures and complete lewis structures. (7th Edition TB 2B.9)
by 804994652
Sun Oct 28, 2018 7:46 pm
Forum: Ionic & Covalent Bonds
Topic: Exceptions to Octet
Replies: 2
Views: 36

Re: Exceptions to Octet

H and He are in the 1s shell which only need 2 e- to be a full shell. Li and Be are metals who tend to lose electrons and become the "noble gas" configuration of He (1s shell).
by 804994652
Sun Oct 28, 2018 7:41 pm
Forum: Formal Charge and Oxidation Numbers
Topic: hw problem 3.51 6th edition
Replies: 2
Views: 93

Re: hw problem 3.51 6th edition

Formal Charge = [# of valence electrons on atom] – [non-bonded electrons + number of bonds]
by 804994652
Sun Oct 28, 2018 7:36 pm
Forum: Ionic & Covalent Bonds
Topic: bound atoms
Replies: 8
Views: 127

Re: bound atoms

Bonded atoms are more stable than unbonded atoms. For example, in the covalent bond of H2, the electrons from the atoms get to be near 2 protons instead of only the one proton it had initially.
by 804994652
Tue Oct 23, 2018 11:19 am
Forum: Properties of Electrons
Topic: Test question
Replies: 6
Views: 216

Re: Test question

Does anyone know what information will be given to us...in terms of formulas and what not. Do we need to know the mass of an electron?
by 804994652
Sun Oct 21, 2018 1:32 pm
Forum: Einstein Equation
Topic: Units
Replies: 10
Views: 403

Re: Units

1 joule = 1kg·m^2·s^-2
If you divide it by s-1. One of the 's' cancels out and you get 1kg·m^2·s^-1.
by 804994652
Sun Oct 21, 2018 1:22 pm
Forum: Trends in The Periodic Table
Topic: Periodic Table Trends
Replies: 5
Views: 110

Re: Periodic Table Trends

ATOMIC RADIUS- increases down and to the left
IONIZATION ENERGY & ELECTRON AFFINITY-increases up and to the right
metals are on the left and nonmentals are on the right
by 804994652
Sun Oct 21, 2018 1:18 pm
Forum: Quantum Numbers and The H-Atom
Topic: Where does this section end in the textbook? [ENDORSED]
Replies: 2
Views: 64

Re: Where does this section end in the textbook? [ENDORSED]

I'm pretty sure that its all the sections under "the quantum world" so 1a, 1b, 1d, 1e, 1f
by 804994652
Sat Oct 13, 2018 9:03 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Negative v. Positive when calculating energy
Replies: 8
Views: 103

Re: Negative v. Positive when calculating energy

Anytime energy is released it is considered negative.
by 804994652
Sat Oct 13, 2018 8:52 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7348
Views: 900291

Re: Post All Chemistry Jokes Here

How often do I tell chemistry jokes? periodically.
by 804994652
Sat Oct 13, 2018 8:48 pm
Forum: Trends in The Periodic Table
Topic: electron affinity [ENDORSED]
Replies: 15
Views: 455

Re: electron affinity [ENDORSED]

As a side note, the general trend for electron affinity is that it increase upwards and from left to right of the periodic table.
by 804994652
Sun Oct 07, 2018 9:01 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Avogadro's Constant Definition
Replies: 7
Views: 342

Re: Avogadro's Constant Definition

I have a similar question. Sometimes questions ask for atoms of Cl2. Does this mean the individual atoms (6.02x10^23) or is it referring to the number of Cl2 atoms in a compound like ZnCl2 has 1 atom of Cl2?
by 804994652
Sun Oct 07, 2018 7:28 pm
Forum: Balancing Chemical Reactions
Topic: H19
Replies: 3
Views: 137

Re: H19

Adding on to what Chathuri said, just because combustion reactions always produce CO2 and H2O, it does not mean it is limited to producing only those compounds. It means it must product those, but if there are other elements involved such as aspartame, N2 is also going to be produced separately.
by 804994652
Sun Oct 07, 2018 7:09 pm
Forum: Limiting Reactant Calculations
Topic: G25
Replies: 1
Views: 82

G25

Does anyone understand G25? It is about doubling the volume of the solution 90 times.

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