Search found 105 matches

by Jacob Villar 2C
Sun Mar 15, 2020 10:53 pm
Forum: Student Social/Study Group
Topic: Number of Chemistry Community Posts
Replies: 33
Views: 556

Re: Number of Chemistry Community Posts

I believe the count starts from your first post in January 2020, and for those that took 14A with Lavelle last quarter, you should have a total of 100 posts by the end I believe.
by Jacob Villar 2C
Sun Mar 15, 2020 10:51 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: kinetics
Replies: 9
Views: 85

Re: kinetics

The reaction would likely require a catalyst to decrease the activation energy and allow the reaction to proceed.
by Jacob Villar 2C
Sun Mar 15, 2020 10:50 pm
Forum: Administrative Questions and Class Announcements
Topic: Chem Community Posts Due Date
Replies: 13
Views: 238

Re: Chem Community Posts Due Date

It's probably due by midnight on Sunday.
by Jacob Villar 2C
Sun Mar 15, 2020 10:49 pm
Forum: Zero Order Reactions
Topic: Units
Replies: 9
Views: 86

Re: Units

Zero order reaction units are in M/s.
by Jacob Villar 2C
Sun Mar 15, 2020 10:48 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: H2O
Replies: 8
Views: 76

Re: H2O

H2O is usually in liquid form, and liquids and solids are not included in ICE tables.
by Jacob Villar 2C
Sun Mar 08, 2020 8:48 pm
Forum: Balancing Redox Reactions
Topic: e- amount
Replies: 9
Views: 47

Re: e- amount

You would multiply the reactions to balance out the number of electrons between the half reactions.
by Jacob Villar 2C
Sun Mar 08, 2020 8:46 pm
Forum: Van't Hoff Equation
Topic: what does it do?
Replies: 13
Views: 204

Re: what does it do?

The Van’t Hoff equation can be used to calculate K when the reaction undergoes temperature changes.
by Jacob Villar 2C
Sun Mar 08, 2020 8:42 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Cell Diagram
Replies: 16
Views: 138

Re: Cell Diagram

Generally, reduction occurs in the cathode and oxidation in the anode.
by Jacob Villar 2C
Sun Mar 08, 2020 8:40 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Platinum
Replies: 10
Views: 45

Re: Platinum

Add platinum when there isn’t a solid electrode already present in the reaction.
by Jacob Villar 2C
Sun Mar 08, 2020 8:39 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Cell potential
Replies: 6
Views: 59

Re: Cell potential

It will dilute the solution, resulting in a change in a Q value due to changes in concentration.
by Jacob Villar 2C
Sun Mar 01, 2020 10:53 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt Bridge
Replies: 12
Views: 80

Re: Salt Bridge

The salt bridge allows the flow of electrons to continue from the anode to the cathode, while also avoiding disrupting the electrical charges.
by Jacob Villar 2C
Sun Mar 01, 2020 10:50 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Anode and Cathode
Replies: 8
Views: 42

Anode and Cathode

Can someone please explain the differences between the anode and cathode?
by Jacob Villar 2C
Sun Mar 01, 2020 10:47 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Degree symbol
Replies: 10
Views: 77

Re: Degree symbol

It means that a given variable or value is present in a reaction that has occurred at standard conditions, say 298 K or 1 atm.
by Jacob Villar 2C
Sun Mar 01, 2020 10:45 pm
Forum: Balancing Redox Reactions
Topic: When to add H+ or H20
Replies: 19
Views: 169

Re: When to add H+ or H20

H2O should be added first, since in doing so you would contribute to balancing the hydrogens and oxygens first. Then, add H+ to balance out the rest of the hydrogens in the acidic solution.
by Jacob Villar 2C
Sun Mar 01, 2020 10:42 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Reducing/oxidizing agent
Replies: 8
Views: 62

Re: Reducing/oxidizing agent

The reducing agent is oxidized because it gives its electron to another substance, thereby reducing said substance. Thus, through vice versa, the oxidizing agent is reduced by gaining an electron from another substance.
by Jacob Villar 2C
Sun Feb 23, 2020 10:09 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Test 2
Replies: 13
Views: 95

Re: Test 2

Electrochemistry, and the end of thermodynamics that deals more with Gibbs free energy.
by Jacob Villar 2C
Sun Feb 23, 2020 10:08 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Limiting reactant and heat
Replies: 4
Views: 99

Re: Limiting reactant and heat

Since an endothermic reaction needs heat to proceed, the heat added to the system could be thought of as a reactant in itself.
by Jacob Villar 2C
Sun Feb 23, 2020 10:07 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Work
Replies: 5
Views: 51

Re: Work

If a system is losing energy to the surroundings, then work is negative, and if it is gaining energy from the surroundings, then work is positive.
by Jacob Villar 2C
Sun Feb 23, 2020 10:06 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: n
Replies: 13
Views: 123

Re: n

The numbers you listed are values for the gas constant R, not n, which would be moles.
by Jacob Villar 2C
Sun Feb 23, 2020 10:05 pm
Forum: Balancing Redox Reactions
Topic: Reduction?
Replies: 13
Views: 92

Re: Reduction?

Gaining electrons means reduction, so whichever atom has a lower charge is reduced.
by Jacob Villar 2C
Sun Feb 23, 2020 10:04 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Spontaneity
Replies: 8
Views: 72

Re: Spontaneity

Yes, if delta G is negative and cell potential is positive, it means the reaction is spontaneous.
by Jacob Villar 2C
Sun Feb 16, 2020 7:27 pm
Forum: Van't Hoff Equation
Topic: Van Hoff's Constants
Replies: 6
Views: 36

Re: Van Hoff's Constants

Both delta H and delta S are constants.
by Jacob Villar 2C
Sun Feb 16, 2020 7:26 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Gibbs free energy
Replies: 5
Views: 48

Re: Gibbs free energy

Delta G naught is delta G but under standard conditions.
by Jacob Villar 2C
Sun Feb 16, 2020 7:25 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Van't Hoff Equation
Replies: 2
Views: 32

Re: Van't Hoff Equation

Since the Van’t Hoff equation would be used presumably under standard conditions, delta S is constant.
by Jacob Villar 2C
Sun Feb 16, 2020 7:23 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: q of ice and q of water
Replies: 8
Views: 104

Re: q of ice and q of water

Due to conservation of energy, the heat lost by the water must be equal to the heat gained by the ice
by Jacob Villar 2C
Sun Feb 16, 2020 7:21 pm
Forum: Van't Hoff Equation
Topic: delta s
Replies: 9
Views: 58

Re: delta s

Delta S won’t change under standard conditions.
by Jacob Villar 2C
Sun Feb 09, 2020 11:54 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: fractions
Replies: 3
Views: 35

Re: fractions

Adding on, I believe 3/2 is used in the instance of monoatomic gases, and 5/2 for diatomic gases.
by Jacob Villar 2C
Sun Feb 09, 2020 11:50 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: spontaneity
Replies: 18
Views: 105

Re: spontaneity

Delta G (change in Gibbs free energy) would be negative if a spontaneous reaction were to occur.
by Jacob Villar 2C
Sun Feb 09, 2020 11:49 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Cv vs. Cp
Replies: 5
Views: 43

Re: Cv vs. Cp

It depends on the conditions of the system, for example, a system with constant volume would have Cv (notice the subscript v) and a system with a constant pressure would be written as Cp for the molar heat constant.
by Jacob Villar 2C
Sun Feb 09, 2020 11:47 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Intensive
Replies: 8
Views: 59

Re: Intensive

Intensive properties do not depend on the amount of substances in the system, whereas extensive properties would be affected by the mass. Entropy is actually an extensive property.
by Jacob Villar 2C
Sun Feb 09, 2020 11:43 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE BOX
Replies: 27
Views: 206

Re: ICE BOX

When K is less than 10^-3, and you'll notice it is able to be approximated if x/initial concentration is less than 5%
by Jacob Villar 2C
Sun Feb 02, 2020 11:34 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: delta U
Replies: 9
Views: 69

Re: delta U

q + w = delta U
by Jacob Villar 2C
Sun Feb 02, 2020 11:30 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Delta q and delta h
Replies: 5
Views: 39

Re: Delta q and delta h

Q relates to heat transfer, whereas delta H refers to change in enthalpy.
by Jacob Villar 2C
Sun Feb 02, 2020 11:28 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Constant pressure
Replies: 19
Views: 137

Re: Constant pressure

Constant external pressure.
by Jacob Villar 2C
Sun Feb 02, 2020 11:20 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Changing the energy of a system
Replies: 9
Views: 54

Re: Changing the energy of a system

Heat, mass flow, and work.
by Jacob Villar 2C
Sun Feb 02, 2020 11:18 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: qp = ΔH?
Replies: 5
Views: 51

Re: qp = ΔH?

When pressure is constant in a system.
by Jacob Villar 2C
Sun Jan 26, 2020 10:55 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE
Replies: 20
Views: 132

Re: ICE

ICE table are used in a problem when you're trying to find the equilibrium concentration.
by Jacob Villar 2C
Sun Jan 26, 2020 10:54 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Percent Ionization
Replies: 12
Views: 70

Re: Percent Ionization

It is x, the equilibrium concentration, divided by the initial concentration.
by Jacob Villar 2C
Sun Jan 26, 2020 10:53 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: The 3 methods
Replies: 4
Views: 47

Re: The 3 methods

Bond enthalpies, since it is taken from the average of multiple molecules.
by Jacob Villar 2C
Sun Jan 26, 2020 10:52 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Pure solids & liquids
Replies: 5
Views: 44

Re: Pure solids & liquids

In chemical reactions, these are substances marked with (s) or (l), which are not included in the equilibrium constant formula, or ICE tables.
by Jacob Villar 2C
Sun Jan 26, 2020 10:51 pm
Forum: *Free Energy of Activation vs Activation Energy
Topic: Spontaneous reactions
Replies: 9
Views: 3163

Re: Spontaneous reactions

Not necessarily, as the equation for Gibbs free energy depends on the values for enthalpy, entropy, and temperature.
by Jacob Villar 2C
Sun Jan 26, 2020 10:49 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction Shifts Left or Right
Replies: 15
Views: 113

Re: Reaction Shifts Left or Right

The reaction will shift towards the reactants.
by Jacob Villar 2C
Sun Jan 19, 2020 11:28 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Different ways to write K
Replies: 3
Views: 30

Re: Different ways to write K

It would help to keep track of what value you are calculating for and to be safe from mixing up equations.
by Jacob Villar 2C
Sun Jan 19, 2020 11:25 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Le Chatelier's principle
Replies: 7
Views: 48

Re: Le Chatelier's principle

It’s a rule that an equilibrium system will shift in reaction to change in order to reach the highest point of stability possible
by Jacob Villar 2C
Sun Jan 19, 2020 11:24 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: lewis structure
Replies: 11
Views: 75

Re: lewis structure

Lavelle sees it has a useful way of visualizing the reactions.
by Jacob Villar 2C
Sun Jan 19, 2020 11:23 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: identifying acids & bases
Replies: 5
Views: 41

Re: identifying acids & bases

Acids donate protons and bases accept protons.
by Jacob Villar 2C
Sun Jan 19, 2020 11:22 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Endothermic Reaction.
Replies: 7
Views: 59

Endothermic Reaction.

How would you determine if a reaction side is endothermic?
by Jacob Villar 2C
Sun Jan 19, 2020 11:20 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction Shifts Left or Right
Replies: 15
Views: 113

Re: Reaction Shifts Left or Right

Reaction will shift to the left.
by Jacob Villar 2C
Sun Jan 19, 2020 11:19 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5% rule
Replies: 8
Views: 63

Re: 5% rule

It’s equilibrium concentration divided by initial concentration.
by Jacob Villar 2C
Sun Jan 12, 2020 9:35 pm
Forum: Ideal Gases
Topic: P=(n/v)RT
Replies: 12
Views: 83

Re: P=(n/v)RT

You can use this equation to calculate for concentration, given that concentration is calculated by dividing moles by volume (n/v).
by Jacob Villar 2C
Sun Jan 12, 2020 9:34 pm
Forum: Ideal Gases
Topic: PV = nRT
Replies: 16
Views: 131

Re: PV = nRT

P - Pressure
V - Volume
n - number of moles
R - ideal gas constant
T - temperature
by Jacob Villar 2C
Sun Jan 12, 2020 9:33 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q>K
Replies: 9
Views: 53

Re: Q>K

If there is more products than reactants, Q will be greater than K, and the reverse reaction will be favored.
by Jacob Villar 2C
Sun Jan 12, 2020 9:32 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: What is this?
Replies: 23
Views: 401

Re: What is this?

Le Chatlier's principle states that an equilibrium system will shift in order to minimize the impact of changes on the system, such as removing products, which will result in a more forward reaction.
by Jacob Villar 2C
Sun Jan 12, 2020 9:30 pm
Forum: Ideal Gases
Topic: The Laws
Replies: 7
Views: 64

Re: The Laws

PV = nRT
by Jacob Villar 2C
Mon Dec 02, 2019 12:01 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Explain VSEPR conceptually
Replies: 12
Views: 129

Re: Explain VSEPR conceptually

VSEPR is a model that shows atomic structure, but with the inclusion of factors such as bond angles and electron repulsion.
by Jacob Villar 2C
Sun Dec 01, 2019 10:55 pm
Forum: Bronsted Acids & Bases
Topic: How to determine if a molecule is a bronsted acid or base?
Replies: 3
Views: 42

Re: How to determine if a molecule is a bronsted acid or base?

A bronsted acid donates protons, whereas a bronsted base accepts protons.
by Jacob Villar 2C
Sun Dec 01, 2019 10:53 pm
Forum: Lewis Acids & Bases
Topic: Weak vs. Strong
Replies: 8
Views: 160

Re: Weak vs. Strong

Stronger acids/bases are completely ionized (dissociated) in solution or water respectively.
by Jacob Villar 2C
Sun Dec 01, 2019 10:51 pm
Forum: Sigma & Pi Bonds
Topic: Sigma vs. Pi
Replies: 15
Views: 311

Re: Sigma vs. Pi

Sigma bonds are stronger due to the orbital overlap.
by Jacob Villar 2C
Sun Dec 01, 2019 9:33 pm
Forum: Lewis Acids & Bases
Topic: Strong Acids
Replies: 5
Views: 44

Re: Strong Acids

Long bonds attribute to stronger acids, since they are weaker bonds, and therefore, the acids can be dissociated to a greater degree.
by Jacob Villar 2C
Sun Dec 01, 2019 9:28 pm
Forum: Resonance Structures
Topic: Formal Charge Question
Replies: 15
Views: 283

Re: Formal Charge Question

Yeah the resonance structures should amount to the same overall charge.
by Jacob Villar 2C
Sun Nov 24, 2019 11:35 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: AXE Format
Replies: 34
Views: 220

Re: AXE Format

I think writing simply X or E would be sufficient.
by Jacob Villar 2C
Sun Nov 24, 2019 11:34 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: t shape and see saw
Replies: 6
Views: 45

Re: t shape and see saw

It depends on bonding pairs vs lone pairs in an atom, as seesaw has 4 bonding pairs, but 1 lone pair, whereas t-shape only has 3 bonding pairs, but 2 lone pairs.
by Jacob Villar 2C
Sun Nov 24, 2019 11:30 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Hydrogen Bonding
Replies: 13
Views: 110

Re: Hydrogen Bonding

Yes, since hydrogen bonds form with the elements N, O, and F, and these are more electronegative atoms.
by Jacob Villar 2C
Sun Nov 24, 2019 11:07 pm
Forum: Resonance Structures
Topic: Lone Pairs
Replies: 3
Views: 120

Re: Lone Pairs

They arrange themselves to experience as small amount of repulsion as possible.
by Jacob Villar 2C
Sun Nov 17, 2019 10:21 pm
Forum: Dipole Moments
Topic: Polarity
Replies: 7
Views: 84

Re: Polarity

Since CCl4 is a symmetrical tetrahedral shape, the dipole moments do cancel out.
by Jacob Villar 2C
Sun Nov 17, 2019 10:09 pm
Forum: Dipole Moments
Topic: Cancelling dipole moments
Replies: 9
Views: 181

Re: Cancelling dipole moments

A dipole moment can be considered cancellable if the dipole moments move in opposite directions, and their magnitude is the same.
by Jacob Villar 2C
Sun Nov 17, 2019 9:50 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 7
Views: 72

Re: Bond Angles

The lone pairs located on a central atom will repel the electrons located within covalent bonds, thus decreasing the bond angles.
by Jacob Villar 2C
Sun Nov 17, 2019 9:46 pm
Forum: Bond Lengths & Energies
Topic: Electron Density
Replies: 10
Views: 160

Re: Electron Density

Yes, and they can play a role in the shape of a molecule in changing the angles between atoms.
by Jacob Villar 2C
Sun Nov 17, 2019 9:45 pm
Forum: Bond Lengths & Energies
Topic: Shorter bond lengths
Replies: 12
Views: 105

Re: Shorter bond lengths

Since there is a greater amount of electrons involved in bonding, the atoms are able to pull closer together, creating a shorter bond length.
by Jacob Villar 2C
Sun Nov 17, 2019 9:41 pm
Forum: Resonance Structures
Topic: Formal Charge Question
Replies: 15
Views: 283

Re: Formal Charge Question

The total formal charge should be equal between resonance structures, although the charges of the individual atoms may differ.
by Jacob Villar 2C
Sun Nov 10, 2019 11:00 pm
Forum: Bond Lengths & Energies
Topic: Dissociation Energy
Replies: 9
Views: 62

Re: Dissociation Energy

Energy is absorbed to be able to break bonds.
by Jacob Villar 2C
Sun Nov 10, 2019 10:57 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Writing e- Configurations
Replies: 15
Views: 173

Re: Writing e- Configurations

Unless specifically stated to write out the full electron configuration, I believe writing the configuration with the noble gas abbreviation would suffice.
by Jacob Villar 2C
Sun Nov 10, 2019 10:55 pm
Forum: Electronegativity
Topic: Iodine
Replies: 6
Views: 60

Re: Iodine

The London dispersion forces within I2 are much stronger due to its larger atomic radius.
by Jacob Villar 2C
Sun Nov 10, 2019 10:54 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: London Forces
Replies: 3
Views: 40

London Forces

I just want to clarify based on the lecture from Friday, but London forces occur in all molecules/atoms right?
by Jacob Villar 2C
Sun Nov 10, 2019 10:51 pm
Forum: Bond Lengths & Energies
Topic: Bond lengths and strength
Replies: 4
Views: 34

Re: Bond lengths and strength

The extra electrons in the double bonds attract the atoms closer together, thereby reducing the length of the double bonds, yet also increasing its strength.
by Jacob Villar 2C
Sun Nov 10, 2019 10:50 pm
Forum: Formal Charge and Oxidation Numbers
Topic: central atom
Replies: 21
Views: 190

Re: central atom

At a formal charge of zero, the atom would be the most stable, so yes.
by Jacob Villar 2C
Sun Nov 03, 2019 10:14 pm
Forum: Dipole Moments
Topic: Dipole Arrow
Replies: 5
Views: 45

Re: Dipole Arrow

In chemistry, it is pointed towards the negative dipole.
by Jacob Villar 2C
Sun Nov 03, 2019 10:06 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent Character
Replies: 3
Views: 33

Covalent Character

Can someone explain to me what exactly covalent character is, what factors affect how great it is, and what the result of a high or low covalent character is?
by Jacob Villar 2C
Sun Nov 03, 2019 10:02 pm
Forum: Bond Lengths & Energies
Topic: Strength of Bonds
Replies: 16
Views: 154

Re: Strength of Bonds

Shorter bonds are generally stronger, and longer bonds tend to be weaker.
by Jacob Villar 2C
Sun Nov 03, 2019 10:01 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Chemical Equations
Replies: 4
Views: 147

Re: Balancing Chemical Equations

I believe that if you put these coefficients (from left to right) it should be balanced: 6, 10, 5, 3, 6, 9.
by Jacob Villar 2C
Sun Nov 03, 2019 9:56 pm
Forum: Sigma & Pi Bonds
Topic: Double bond
Replies: 15
Views: 170

Re: Double bond

Most often double bonds are drawn in order to keep in line with the octet rule.
by Jacob Villar 2C
Sun Oct 27, 2019 11:45 pm
Forum: Lewis Structures
Topic: Lone Pairs
Replies: 12
Views: 110

Re: Lone Pairs

Lone pairs are the dots on a lewis structure that do not form bonds, for example, on an atom, they would be the two dots on the side.
by Jacob Villar 2C
Sun Oct 27, 2019 10:38 pm
Forum: Octet Exceptions
Topic: Exceptions
Replies: 3
Views: 58

Re: Exceptions

H, He, Li, and B are exceptions to the octet rule because their amount of electrons are only enough to reach the 1s orbital, and therefore, the octet rule cannot be applied in these circumstances.
by Jacob Villar 2C
Sun Oct 27, 2019 10:33 pm
Forum: Ionic & Covalent Bonds
Topic: Single bond vs. Double bond vs. Triple bond
Replies: 3
Views: 59

Re: Single bond vs. Double bond vs. Triple bond

I believe that due to the greater amount of attraction between electrons in double bonds and triple bonds, this causes the bond length to be shorter than that of a single bond.
by Jacob Villar 2C
Sun Oct 27, 2019 10:25 pm
Forum: Sigma & Pi Bonds
Topic: Double bond
Replies: 15
Views: 170

Re: Double bond

Sometimes, the octet rule will not be satisfied with simply using single bonds, and therefore double bonds would be necessary to satisfy this rule.
by Jacob Villar 2C
Sun Oct 27, 2019 10:20 pm
Forum: Lewis Structures
Topic: Choosing the central atom
Replies: 16
Views: 162

Re: Choosing the central atom

The atom with the lowest ionization energy is the central atom.
by Jacob Villar 2C
Sun Oct 27, 2019 10:18 pm
Forum: Ionic & Covalent Bonds
Topic: Ionization Energy Unit
Replies: 6
Views: 64

Re: Ionization Energy Unit

kJ/mol, kilojoules per mole
by Jacob Villar 2C
Sun Oct 20, 2019 10:28 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Atomic Orbitals
Replies: 3
Views: 48

Re: Atomic Orbitals

We will learn more about this later, but valence electrons (electrons sitting on the outermost orbital), are important to the bonding between atoms.
by Jacob Villar 2C
Sun Oct 20, 2019 10:16 pm
Forum: Empirical & Molecular Formulas
Topic: Molecular to Empirical Formula
Replies: 10
Views: 338

Re: Molecular to Empirical Formula

You would have to find the molar mass using the empirical formula, and divide the given molar mass by this value. Then with the answer, which is usually a whole number, multiply all the subscripts of the empirical formula by the molar mass ratio.
by Jacob Villar 2C
Sun Oct 20, 2019 10:01 pm
Forum: DeBroglie Equation
Topic: Unit Conversion
Replies: 5
Views: 73

Re: Unit Conversion

Since mega- translates to 10^6, 1 Hz would translate to 1*10^6 mHz
by Jacob Villar 2C
Sun Oct 20, 2019 9:58 pm
Forum: Quantum Numbers and The H-Atom
Topic: Magnetic Quantum Number
Replies: 5
Views: 59

Re: Magnetic Quantum Number

The magnetic quantum number labels the different orbitals of a subs [censored].
by Jacob Villar 2C
Sun Oct 20, 2019 9:54 pm
Forum: Properties of Light
Topic: What are the units of hertz
Replies: 41
Views: 393

Re: What are the units of hertz

1 Hz is counted as 1 cycle per second
by Jacob Villar 2C
Sun Oct 13, 2019 11:34 pm
Forum: Significant Figures
Topic: sig figs and periodic tables
Replies: 11
Views: 346

Re: sig figs and periodic tables

Should we bet using sig figs based on given number values (ex: if the problem gives us 250 mL, we use 3 sig figs) or should we be basing the amount of sig figs we use on calculations as we go?
by Jacob Villar 2C
Sun Oct 13, 2019 8:14 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 118
Views: 31217

Re: Final Jitters

I like to let out a big breath before taking the test to help clear my system of anxiety, and often times I'll chew gum because it helps me focus on the material rather than other small things going around in the room, which also saves time for more work on problems.
by Jacob Villar 2C
Sun Oct 13, 2019 8:11 pm
Forum: Balancing Chemical Reactions
Topic: Writing out equations
Replies: 9
Views: 264

Re: Writing out equations

The Hill system shows that the order of listing elements starts with carbon atoms, then hydrogen atoms, and then all other atoms in alphabetical order.
by Jacob Villar 2C
Sun Oct 13, 2019 8:07 pm
Forum: SI Units, Unit Conversions
Topic: knowing how many sig figs to use
Replies: 17
Views: 231

Re: knowing how many sig figs to use

I think that it is proper to use the same amount of sig figs throughout the entire problem, so that there is consistency with each preceding calculation. Especially with given units, the sig figs in your final answer should likely match the amount of sig figs with these given numbers.
by Jacob Villar 2C
Sun Oct 13, 2019 7:57 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Angstrom's Constant
Replies: 5
Views: 179

Angstrom's Constant

So I know that the equivalent of an Angstrom unit is 1A = 10^-10 m, but how would you convert to other significant units such as centimeters or picometers? DO you multiply by tens when converting to smaller units, or do you multiply by tens when converting to larger units
by Jacob Villar 2C
Sun Oct 06, 2019 10:43 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Reactions
Replies: 25
Views: 555

Re: Balancing Reactions

According to the Law of Conservation of Mass, matter cannot be created nor destroyed, and therefore, when balancing a reaction, you must have the same amount of moles on both the reactants and products side in accordance with the conservation of mass.

Go to advanced search