## Search found 103 matches

Fri Mar 13, 2020 10:08 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Slow Step Determination
Replies: 5
Views: 100

### Re: Slow Step Determination

I'm pretty sure it should be given
Fri Mar 13, 2020 10:08 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Identification
Replies: 4
Views: 113

### Re: Identification

I think you just have to know if it's pure or not
Fri Mar 13, 2020 10:06 pm
Forum: Administrative Questions and Class Announcements
Replies: 15
Views: 353

### Re: take home FINAL DEADLINE

He hasn't explicitly stated when we need to submit the final yet
Fri Mar 13, 2020 10:04 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Catalysts
Replies: 5
Views: 59

### Re: Catalysts

It means the catalyst is not consumed during the reaction
Fri Mar 13, 2020 10:03 pm
Forum: General Rate Laws
Topic: Temperature and kinetics
Replies: 5
Views: 103

### Re: Temperature and kinetics

Yes at higher temperatures, molecules have higher kinetic energy
Fri Mar 13, 2020 10:02 pm
Forum: First Order Reactions
Topic: Units for t
Replies: 13
Views: 148

### Re: Units for t

The SI units for time is seconds
Fri Mar 13, 2020 10:01 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Delta S total
Replies: 3
Views: 96

### Re: Delta S total

The total entropy is the entropy of the surroundings plus the entropy of the system
Fri Mar 13, 2020 10:00 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Catalysts
Replies: 3
Views: 50

### Re: Catalysts

I think different types of catalysts use different methods to lower the activation energy
Fri Mar 13, 2020 9:58 pm
Forum: Zero Order Reactions
Topic: Catalyst
Replies: 4
Views: 121

### Re: Catalyst

No a zero order reaction won't be influenced by a catalyst
Fri Mar 13, 2020 9:56 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6.45
Replies: 3
Views: 53

### Re: 6.45

The reduction table in the back of the book shows you which metals will be reduced
Fri Mar 13, 2020 9:54 pm
Forum: General Rate Laws
Topic: Instantaneous Rate
Replies: 2
Views: 52

### Re: Instantaneous Rate

The instantaneous rate is the rate at any given time, the rate is given by the tangent line at that time
Fri Mar 13, 2020 9:52 pm
Forum: Balancing Redox Reactions
Topic: Oxidation number
Replies: 12
Views: 269

### Re: Oxidation number

The oxidation number change in a chemical reaction show what is being reduced and oxidized
Wed Mar 11, 2020 4:41 pm
Forum: First Order Reactions
Topic: rate constants
Replies: 19
Views: 323

### Re: rate constants

the rate constant is always positive
Wed Mar 11, 2020 4:39 pm
Forum: General Rate Laws
Topic: Rate limiting step
Replies: 13
Views: 162

### Re: Rate limiting step

it's the slowest step in a reaction
Wed Mar 11, 2020 4:38 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: finding k
Replies: 3
Views: 43

### Re: finding k

You'll likely need to be given the rate law or experimental data
Wed Mar 11, 2020 4:37 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Change in Ecell
Replies: 5
Views: 78

### Re: Change in Ecell

Increasing the size of the metal does not change the cell potential
Wed Mar 11, 2020 4:36 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: dilutions and Ecell
Replies: 8
Views: 152

### Re: dilutions and Ecell

If it's a cathode solution (like on test 2) then diluting it will decrease cell potential
Wed Mar 11, 2020 4:34 pm
Forum: *Enzyme Kinetics
Topic: Do we need to know enzyme kinetics for the final? [ENDORSED]
Replies: 4
Views: 447

### Re: Do we need to know enzyme kinetics for the final?[ENDORSED]

You should know that enzymes can act as catalysts
Wed Mar 11, 2020 4:32 pm
Forum: General Rate Laws
Topic: 7A.3
Replies: 5
Views: 100

### Re: 7A.3

0.44 is not the rate constant but the actual rate so you would multiply the number of oxygen's by 0.44
Mon Mar 09, 2020 3:50 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: purpose
Replies: 4
Views: 77

### Re: purpose

It relates the rate constant k to activation energy Ae and temperature T
Mon Mar 09, 2020 3:47 pm
Forum: General Rate Laws
Topic: overall order
Replies: 5
Views: 50

### Re: overall order

You'll have to find the order of the individual reactants then add them up
Mon Mar 09, 2020 3:46 pm
Forum: Second Order Reactions
Topic: linear graph
Replies: 7
Views: 162

### Re: linear graph

1/[A] vs time
Mon Mar 09, 2020 3:45 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: Slow Step
Replies: 4
Views: 46

### Re: Slow Step

You will most likely not need to determine which step is the slow step
Mon Mar 09, 2020 3:45 pm
Forum: General Science Questions
Replies: 23
Views: 601

Probably during dicussion
Mon Mar 09, 2020 3:44 pm
Forum: General Rate Laws
Topic: 7A3
Replies: 2
Views: 65

### Re: 7A3

Since the equation has 3 moles of O2 on the reactant side, the rate at which oxygen reacts will be 3 times the rate of reaction
Similarly, since the equation has 2moles of H2O on the product side, the rate at which water forms will be 2 times the rate of reaction
Mon Mar 09, 2020 3:42 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: k'
Replies: 6
Views: 85

### Re: k'

it is the rate constant of the reverse reaction
Mon Feb 10, 2020 4:59 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Isothermal
Replies: 9
Views: 90

### Re: Isothermal

Isothermal systems have constant temperature, this does not mean the same as reversible
Mon Feb 10, 2020 4:52 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: spontaneity
Replies: 18
Views: 171

### Re: spontaneity

if delta G is negative the reaction is spontaneous
Mon Feb 10, 2020 4:49 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Spontaneous delta G
Replies: 7
Views: 69

### Re: Spontaneous delta G

finding the temperature at delta G=0 gives the minimum temperature for the reaction to be spontaneous
Mon Feb 10, 2020 4:41 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: qp=deltaH
Replies: 6
Views: 85

### Re: qp=deltaH

q = deltaH at constant pressure
Mon Feb 10, 2020 4:40 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: q=mCdeltaT vs q=nCdeltaT
Replies: 2
Views: 36

### Re: q=mCdeltaT vs q=nCdeltaT

use q=mCdeltaT when you're given the mass and use q=nCdeltaT when you're given the moles
Sun Feb 02, 2020 8:33 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Positive or negative work?
Replies: 8
Views: 87

### Re: Positive or negative work?

If work is done on the system it is positive, if the system is doing work its surroundings work is negative
Sun Feb 02, 2020 8:31 pm
Forum: Ideal Gases
Topic: PV=nRT
Replies: 12
Views: 173

### Re: PV=nRT

P is pressure, V is volume, n is # of moles of gas, R is the gas constant, T is temperature
Sun Feb 02, 2020 8:29 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Temperature
Replies: 14
Views: 177

### Re: Temperature

Exothermic
Sun Feb 02, 2020 8:28 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Pressure in an open beaker
Replies: 12
Views: 108

### Re: Pressure in an open beaker

Pressure in an open beaker is always constant since there isn't a volume to drop or increase pressure
Sun Feb 02, 2020 8:28 pm
Forum: General Science Questions
Topic: Extra Credit
Replies: 19
Views: 293

### Re: Extra Credit

I don't think so.
Mon Jan 27, 2020 3:08 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Exothermic reaction
Replies: 18
Views: 267

### Re: Exothermic reaction

if temp increases then the reaction will shift to the left, if temp decreases then the reaction will shift to the right
Mon Jan 27, 2020 3:07 am
Forum: Administrative Questions and Class Announcements
Replies: 18
Views: 245

I believe they'll give partial credit if you use the right steps
Mon Jan 27, 2020 3:06 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: pKa to Kb
Replies: 12
Views: 145

### Re: pKa to Kb

pKa + pKb = 14, then use pKb to solve for Kb
Mon Jan 27, 2020 3:05 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction Shifts Left or Right
Replies: 15
Views: 176

### Re: Reaction Shifts Left or Right

the reaction will shift left
Mon Jan 27, 2020 3:04 am
Forum: Administrative Questions and Class Announcements
Topic: homework for week 4
Replies: 11
Views: 129

### Re: homework for week 4

I'm pretty sure the thermodynamics section
Sun Jan 19, 2020 9:12 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: pKa
Replies: 13
Views: 91

### Re: pKa

A stronger acid will have a lower pKa
Sun Jan 19, 2020 9:12 pm
Forum: General Science Questions
Topic: test 1
Replies: 8
Views: 101

### Re: test 1

The test is during your discussion session on week 3
Sun Jan 19, 2020 9:09 pm
Forum: General Science Questions
Topic: Acids
Replies: 3
Views: 54

### Re: Acids

Lewis acids are proton acceptors while Bronsted acids are proton donors
Sun Jan 19, 2020 9:08 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Le Chatelier's Principle
Replies: 7
Views: 58

### Re: Le Chatelier's Principle

It helps us predict how a reaction will react when a physical change occurs
Sun Jan 19, 2020 9:05 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Relationship between pressure and volume
Replies: 10
Views: 93

### Re: Relationship between pressure and volume

Yes they're inversely proportional
Sun Jan 12, 2020 9:18 pm
Forum: Ideal Gases
Topic: P=(n/v)RT
Replies: 12
Views: 136

### Re: P=(n/v)RT

Writing (n/V)RT is the same as nRT/V
Sun Jan 12, 2020 9:16 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q>K
Replies: 9
Views: 82

### Re: Q>K

If the ratio of products to reactants is larger than that of the equilibrium constant, then Q>K
Sun Jan 12, 2020 9:09 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Calculating Q
Replies: 16
Views: 226

### Re: Calculating Q

Since the activity of solids and liquids are equal to 1, they aren't included in the calculation of Q and K, this leaves only gases and aqueous substances
Sun Jan 12, 2020 9:04 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Concentration
Replies: 5
Views: 36

### Re: Concentration

If all other conditions remain the same, the equilibrium constant won't change
Sun Jan 12, 2020 9:02 pm
Forum: Ideal Gases
Topic: ICE Table
Replies: 9
Views: 108

### Re: ICE Table

If the forward reaction is favored, then reactants will have a negative change and products will have a negative change, and vice versa when the reverse reaction is favored
Sun Dec 08, 2019 6:49 pm
Forum: Naming
Topic: Chelating
Replies: 3
Views: 149

### Re: Chelating

If it has the structure binding site-spacer-spacer-binding site then it is typically chelating
Sun Dec 08, 2019 6:47 pm
Forum: Octet Exceptions
Topic: Octet exception
Replies: 14
Views: 512

### Re: Octet exception

Elements with the third energy shell and on since the d-orbital can also have electrons
Sun Dec 08, 2019 6:45 pm
Forum: Naming
Topic: -ate
Replies: 11
Views: 286

### Re: -ate

You don't need to add anything for positive ions or neutral molecules
Sun Dec 08, 2019 6:44 pm
Forum: Amphoteric Compounds
Topic: Amphiprotic
Replies: 7
Views: 193

### Re: Amphiprotic

they can act as both an acid and a base
Sun Dec 08, 2019 6:44 pm
Forum: Hybridization
Topic: double and triple bonds
Replies: 6
Views: 255

### Re: double and triple bonds

pi bonds in double and triple bonds don't hybridize
Sun Dec 01, 2019 6:22 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: 6C.19
Replies: 1
Views: 38

### Re: 6C.19

HNO3 is stronger since it’s conjugate base NO3- is more stable than the conjugate base of HNO2
Sun Dec 01, 2019 6:19 pm
Forum: Bronsted Acids & Bases
Topic: Conjugate acids and bases
Replies: 5
Views: 110

### Re: Conjugate acids and bases

Conjugate acids are bronsted bases with an H+
Conjugate vases are bronsted acids without an H+
Sun Dec 01, 2019 6:12 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Drawing sigma & Pi bonds
Replies: 7
Views: 214

### Re: Drawing sigma & Pi bonds

You can represent end to end by drawing 2 infinity signs next to each other and represent side to side by drawing two 8’s next to each other
Sun Dec 01, 2019 6:05 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: pH calcuations
Replies: 8
Views: 107

### Re: pH calcuations

I believe so
Sun Dec 01, 2019 6:03 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: H2SO4
Replies: 2
Views: 42

### Re: H2SO4

Yes the concentration of H+ would be double that of H2SO4
Sun Nov 24, 2019 3:50 pm
Forum: Naming
Topic: Order
Replies: 4
Views: 75

### Re: Order

The transition metal cation comes before the anion
Sun Nov 24, 2019 3:49 pm
Forum: Administrative Questions and Class Announcements
Topic: Focus 9C.1 and 9C.2
Replies: 2
Views: 63

### Re: Focus 9C.1 and 9C.2

9C.1: Coordination Complexes
9C.2: The Shapes of Complexes
Fri Nov 22, 2019 1:12 am
Forum: Determining Molecular Shape (VSEPR)
Topic: name?
Replies: 4
Views: 60

### Re: name?

chrisleung wrote:Yes, they are two names for the same geometry, for molecules with configuration AX2E or AX3E

AX3E would be trigonal pyramidal, AX2E2 would be bent
Fri Nov 22, 2019 1:08 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: london forces
Replies: 9
Views: 101

### Re: london forces

The larger molecule will have stronger London forces
Fri Nov 22, 2019 1:07 am
Forum: Determining Molecular Shape (VSEPR)
Topic: NO Shape and Polarity
Replies: 4
Views: 81

### Re: NO Shape and Polarity

NO is linear, I think it's slightly polar
Mon Nov 18, 2019 12:36 am
Forum: Determining Molecular Shape (VSEPR)
Topic: pentagonal bipyramidal 3 lone pairs?
Replies: 2
Views: 45

### Re: pentagonal bipyramidal 3 lone pairs?

I don't think we would need to know this as it's either super uncommon or not possible
Mon Nov 18, 2019 12:31 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: NH2OH
Replies: 1
Views: 28

### Re: NH2OH

it would be between the oxygen atoms of one molecule and the hydrogen of another
Mon Nov 18, 2019 12:28 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: CH2Cl2
Replies: 1
Views: 38

### Re: CH2Cl2

since the C-H bonds and C-Cl bonds have differing polarities, the molecule will be polar and will have dipole-dipole interactions
Mon Nov 18, 2019 12:26 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: H2SeO4
Replies: 1
Views: 47

### Re: H2SeO4

the dipole between O-H bonds will cause the H to be slightly negative, while the dipole between the Se-O bonds will make the O slightly positive, this causes the H atoms of one molecule to be attracted to the O atoms of another, creating dipole-dipole interactions
Mon Nov 18, 2019 12:21 am
Forum: Dipole Moments
Topic: Intermolecular Forces
Replies: 1
Views: 39

### Re: Intermolecular Forces

London, Dipole-dipole, dipole-induced dipole, ion-dipole, h-bondings, ion-induced dipole
Sun Nov 10, 2019 6:47 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 moment and intermolecular forces
Replies: 3
Views: 79

### Re: dipole moment and intermolecular forces

Dipole moments cause parts of a molecule to be charged, this leads to positively charged parts of one molecule being attracted to negatively charged parts of another, leading to intermolecular forces.
Sun Nov 10, 2019 6:45 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: London vs. dipole-induced-dipole interaction
Replies: 3
Views: 35

### Re: London vs. dipole-induced-dipole interaction

I think they're the same thing
Sun Nov 10, 2019 6:44 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: 3F.3 hw prob
Replies: 1
Views: 27

### Re: 3F.3 hw prob

CH4 and CCl4 won't have dipole-dipole interactions since they don't have permanent dipole moments
Sun Nov 10, 2019 6:41 am
Forum: Dipole Moments
Topic: Dipole Moments
Replies: 3
Views: 44

### Re: Dipole Moments

dipole moments occur when electrons are unequally shared, this can affect intermolecular forces as it makes parts of the molecule positively/negatively charged
Sun Nov 10, 2019 6:39 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: 3F.1 hw prob
Replies: 1
Views: 18

### Re: 3F.1 hw prob

Look at the difference in electronegativity between atoms and look for cases of hydrogen bonding
Sat Nov 02, 2019 6:59 pm
Forum: Lewis Structures
Topic: 2B. 9
Replies: 3
Views: 47

### Re: 2B. 9

It shows that they're bonded through ionic bonds rather than covalent bonds
Sat Nov 02, 2019 6:56 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 2A.3
Replies: 1
Views: 40

### Re: 2A.3

a) [Ar]
b) [Ar]3d^10 4s^2
c) [Kr]4d^5
d) [Ar]3d^10 4s^2
Sat Nov 02, 2019 6:55 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 2A.5
Replies: 1
Views: 45

### Re: 2A.5

a) [Ar]3d^10
b) [Xe]4f^14 5d^10 6s^2
c) [Ar]3d^10;
d) [Xe]4f^14 5d^10
Sat Nov 02, 2019 6:52 pm
Forum: Resonance Structures
Topic: Textbook question 2B.15
Replies: 1
Views: 46

### Re: Textbook question 2B.15

N can't be double bonded to Cl since Cl is a halogen and halogens don't form double bonds
Sat Nov 02, 2019 6:48 pm
Forum: Lewis Structures
Topic: 2B. 3 part d
Replies: 4
Views: 45

### Re: 2B. 3 part d

Br has three bonds (one with each F) and two pairs of lone electrons, while the F's have 3 pairs of lone electrons
Sun Oct 27, 2019 9:33 pm
Forum: Lewis Structures
Topic: VSEPR: E in AXE
Replies: 2
Views: 29

### Re: VSEPR: E in AXE

E represents lone pairs on the central atom
Sun Oct 27, 2019 9:31 pm
Forum: Sigma & Pi Bonds
Topic: Single vs. Double bonds
Replies: 15
Views: 274

### Re: Single vs. Double bonds

Since double bonds are stronger, they pull the atoms closer together and are therefore shorter.
Sun Oct 27, 2019 9:29 pm
Forum: Lewis Structures
Topic: 2C.7
Replies: 2
Views: 38

### Re: 2C.7

a.2 bonding pairs, 2 lone pairs
b.2 bonding pairs, 4 lone pairs
c.3 bonding pairs, 2 lone pairs
d.5 bonding pairs, 1 lone pair
Sun Oct 27, 2019 9:25 pm
Forum: Ionic & Covalent Bonds
Topic: 2A.23
Replies: 2
Views: 52

### Re: 2A.23

a.Mg3As2
b.In2S3
c.AlH3
d.H2Te
e.BiF3
Sun Oct 27, 2019 9:21 pm
Forum: Ionic & Covalent Bonds
Topic: 2A.21
Replies: 4
Views: 80

### Re: 2A.21

a.[Ar]
b.[Kr]5s^2 4d^10
c.[Xe]
d.[Ar]3d^8

no unpaired electrons for all
Sat Oct 19, 2019 9:31 pm
Forum: Photoelectric Effect
Topic: E = pc vs E= mv^2/2
Replies: 2
Views: 44

### Re: E = pc vs E= mv^2/2

E=pc=mc^2 only applies to em radiation

E=mv^2/2 is used for kinetic energy of an object
Sat Oct 19, 2019 7:53 pm
Forum: Properties of Electrons
Topic: Electron structures
Replies: 4
Views: 95

### Re: Electron structures

Electrons are paired if they're in the same orbital and parallel if they're in separate orbitals and have the same spin
Sat Oct 19, 2019 3:00 pm
Forum: DeBroglie Equation
Topic: 1B. 19 Homework Help
Replies: 1
Views: 40

### Re: 1B. 19 Homework Help

I used the ones from the chem website

Mass of neutron = 1.674 927 × 10^−27 kg

Mass of proton = 1.672 622 × 10^−27 kg
Sat Oct 19, 2019 2:58 pm
Forum: General Science Questions
Topic: Midterm
Replies: 12
Views: 263

### Re: Midterm

6 – 8pm, Wednesday November 6
Sat Oct 19, 2019 2:55 pm
Forum: Einstein Equation
Topic: Focus 1B.5 Homework.. Electron Volts
Replies: 2
Views: 71

### Re: Focus 1B.5 Homework.. Electron Volts

1 eV = 1.602 × 10^-19 J
Sat Oct 12, 2019 3:47 pm
Forum: DeBroglie Equation
Topic: Wave Properties of Electrons and the De Broglie Equation Post-Module Assessment
Replies: 1
Views: 28

### Re: Wave Properties of Electrons and the De Broglie Equation Post-Module Assessment

wavelength = h/(mv)

if wavelength is shorter than 10^-15m it is undetectable
Sat Oct 12, 2019 3:40 pm
Forum: Properties of Light
Topic: Wavelength
Replies: 4
Views: 74

### Re: Wavelength

since the speed of light is always the same c = 3.0*10^8 and c=wavelength * frequency, as wavelength decreases frequency must increase and the same idea applies to energy since frequency and energy are directly related
Sat Oct 12, 2019 3:29 pm
Forum: Properties of Light
Topic: Homework B9
Replies: 1
Views: 44

### Re: Homework B9

find number of joules from the light
32J/s * 2.0s = 64J

then divide joules by the energy per photon
64J/(4.7*10^-19) = 1.4*10^20

1.4*10^20/(6.022*10^23) = 2.3*10^-4 mol photon
Sat Oct 12, 2019 3:19 pm
Forum: Properties of Electrons
Topic: Speed of an Electron
Replies: 3
Views: 91

### Re: Speed of an Electron

I think it's reasonable as long as it's lower than the speed of light
Sat Oct 12, 2019 3:16 pm
Forum: Properties of Light
Topic: Textbook 1B.15
Replies: 1
Views: 36

### Re: Textbook 1B.15

E(photon)=1.66*10^-17+KE(electron)= 1.66*10^-17J + 0.5 * (9.11*10^-31kg) * (3.6*10^6m/s)^2 = 2.25*10^-17J

then you can use the energy of the photon to find the wavelength using E=hv
Sun Oct 06, 2019 1:49 pm
Forum: Molarity, Solutions, Dilutions
Topic: Preparing solutions
Replies: 1
Views: 56

### Re: Preparing solutions

I don't think so
Thu Oct 03, 2019 4:59 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Lab experiments- accuracy vs precision
Replies: 7
Views: 155

### Re: Lab experiments- accuracy vs precision

If your experiment is inaccurate yet precise it may indicate that there is a problem with the devices/methods you are using to conduct your experiment
Thu Oct 03, 2019 4:57 pm
Forum: Limiting Reactant Calculations
Topic: Fundamentals M.17
Replies: 6
Views: 138

### Re: Fundamentals M.17

Darren Nguyen 1F wrote:
Samuel Tzeng 1H wrote:Molar mass of XA = total mass - mass of H2O

How do I get total mass?

It's the molar mass of HA + XOH = (250+125)

Sorry I meant total molar mass - molar mass of H2O
Thu Oct 03, 2019 4:53 pm
Forum: Balancing Chemical Reactions
Topic: Fundamentals L39
Replies: 2
Views: 101

### Re: Fundamentals L39

Start off by finding moles of tin and oxygen

Sn: 1.50g Sn / 118.71g/mol = .01264 mol Sn
O: (28.35g - 26.45g - 1.50g) / 16.00g/mol = 0.025 mol O

With this you can tell the empirical formula is SnO2

The oxide would be Tin(IV) Oxide since each oxygen has a -2 charge so the tin must have a +4 charge