Search found 51 matches

by Alessia Renna 1D
Sat Dec 12, 2020 7:53 am
Forum: Trends in The Periodic Table
Topic: Inert-Pair Effect?
Replies: 1
Views: 27

Inert-Pair Effect?

Do we need to know about the Inert-Pair Effect? If so, can someone please explain it?
by Alessia Renna 1D
Sat Dec 12, 2020 7:49 am
Forum: Polyprotic Acids & Bases
Topic: Polyprotic Acids and Bases
Replies: 2
Views: 43

Polyprotic Acids and Bases

Does anyone know specifically what we should know regarding this for the final?
by Alessia Renna 1D
Sat Dec 12, 2020 7:46 am
Forum: Conjugate Acids & Bases
Topic: Oxyacids
Replies: 8
Views: 51

Oxyacids

Can someone please explain oxyacids?
by Alessia Renna 1D
Sat Dec 12, 2020 7:43 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Steric #
Replies: 3
Views: 49

Steric #

Is this correct: The steric # is the total amount of bonds/lone pairs for the central atom?
by Alessia Renna 1D
Tue Dec 08, 2020 3:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: wedge and dash
Replies: 14
Views: 122

wedge and dash

can someone explain the wedge and dash notation?
by Alessia Renna 1D
Sun Dec 06, 2020 9:44 pm
Forum: Trends in The Periodic Table
Topic: Electron Affinity
Replies: 9
Views: 119

Re: Electron Affinity

The one to the right would have a higher electron affinity!
by Alessia Renna 1D
Sun Dec 06, 2020 9:44 pm
Forum: Limiting Reactant Calculations
Topic: Cl vs Cl2
Replies: 9
Views: 120

Re: Cl vs Cl2

Correct! Cl2 is chlorine gas!
by Alessia Renna 1D
Sun Dec 06, 2020 9:43 pm
Forum: Empirical & Molecular Formulas
Topic: Periodic Table and Calculations
Replies: 20
Views: 172

Re: Periodic Table and Calculations

I use a graphing calculator and the periodic table from Lavelle's website!
by Alessia Renna 1D
Sun Dec 06, 2020 9:42 pm
Forum: Significant Figures
Topic: When should I start looking at sig figs?
Replies: 31
Views: 262

Re: When should I start looking at sig figs?

I think just using sig figs in your final answer is fine!
by Alessia Renna 1D
Sun Dec 06, 2020 9:41 pm
Forum: SI Units, Unit Conversions
Topic: unit conversions
Replies: 24
Views: 286

Re: unit conversions

I would say to just do 10^x
by Alessia Renna 1D
Mon Nov 30, 2020 9:50 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Sigma and Pi Bonds
Replies: 31
Views: 448

Re: Sigma and Pi Bonds

the order does not matter as long as you know how many sigma and pi bonds there are
by Alessia Renna 1D
Wed Nov 25, 2020 12:43 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: What does delocalized π bond mean?
Replies: 18
Views: 151

Re: What does delocalized π bond mean?

delocalized pi bonds are formed when pi orbitals extend across two or more atoms in one molecule
by Alessia Renna 1D
Wed Nov 25, 2020 11:59 am
Forum: Determining Molecular Shape (VSEPR)
Topic: coplanar?
Replies: 9
Views: 73

coplanar?

what does it mean for the atoms in a molecule to be coplanar?
by Alessia Renna 1D
Wed Nov 25, 2020 11:06 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Shape Names
Replies: 50
Views: 328

Re: Shape Names

yes it would be angular/bent (or AX2E2)
by Alessia Renna 1D
Wed Nov 25, 2020 11:04 am
Forum: Determining Molecular Shape (VSEPR)
Topic: sapling HW question three
Replies: 5
Views: 69

Re: sapling HW question three

the smallest bond angle would be 109.5 because the molecule is AX2E2 (central atom, 2 outer atoms, 2 lone pairs) meaning the shape is angular/bent!
by Alessia Renna 1D
Sun Nov 22, 2020 3:58 pm
Forum: Octet Exceptions
Topic: Octet Exceptions Question
Replies: 5
Views: 69

Re: Octet Exceptions Question

It does mean that it can have more than four bonds as four bonds typically = 8 electrons
by Alessia Renna 1D
Sun Nov 22, 2020 3:55 pm
Forum: Electronegativity
Topic: Periodic trend
Replies: 17
Views: 192

Re: Periodic trend

Yes that is correct! This is a diagram that really helped me: https://www.google.com/search?q=electronegativity+trend&sxsrf=ALeKk03wiJfNPEEDhLrmFKSurJT5txztVw:1606089292926&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiF76DurJftAhVwSzABHX_7CN0Q_AUoAXoECB0QAw&biw=1680&bih=850#imgr...
by Alessia Renna 1D
Sun Nov 22, 2020 3:54 pm
Forum: Bond Lengths & Energies
Topic: Bond Length vs Size of Molecule
Replies: 14
Views: 151

Re: Bond Length vs Size of Molecule

longer bonds are weaker but type of bonding (like london dispersion forces) can influence boiling point as well!
by Alessia Renna 1D
Tue Nov 17, 2020 5:31 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Can someone please explain this outline bullet?
Replies: 1
Views: 47

Can someone please explain this outline bullet?

Describe the factors affecting the energy of an electron in a many-electron atom.

Can anyone explain this? Thank you!
by Alessia Renna 1D
Tue Nov 17, 2020 12:40 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Ground State Electron Configuration (Textbook: 2A.3 #d)
Replies: 1
Views: 33

Ground State Electron Configuration (Textbook: 2A.3 #d)

What would the ground state electron configuration for Ge2+ be?
by Alessia Renna 1D
Sun Nov 15, 2020 12:54 pm
Forum: Lewis Structures
Topic: Nitrite vs Nitrate
Replies: 17
Views: 154

Re: Nitrite vs Nitrate

Nitrite and Nitrate are both polyatomic ions! Usually you need to memorize these but I think they will just be given in the question on the exam. A trick that my tutor taught me is that the sub number on polyatomic ions that end in "-ite" will always be one less than the "-ate" v...
by Alessia Renna 1D
Sat Nov 14, 2020 3:11 pm
Forum: Resonance Structures
Topic: plausible perchlorate ion
Replies: 3
Views: 50

Re: plausible perchlorate ion

The structure that has the most non-zero charges is preferred.
by Alessia Renna 1D
Sat Nov 14, 2020 12:41 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Oxidation Number
Replies: 11
Views: 140

Re: Oxidation Number

Because ClO4- has a charge, the oxidation numbers of each element in the compound must add up to equal the charge. We know that oxygen has an oxidation number of -2, and there are 4 Oxygens in ClO4- so O = -8. Because the charge is -1, we know that Cl must be +7 becuase 7 + -8 = -1
by Alessia Renna 1D
Sat Nov 14, 2020 12:16 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Number of Resonance Structures
Replies: 7
Views: 102

Re: Number of Resonance Structures

A resonance structure means that you can draw two or more Lewis structures for a molecule. You can do this when you are able to change the locations of the electrons within the structure (I.E. if there are two O molecules in a structure and one has a double bond, you can form the resonance structure...
by Alessia Renna 1D
Sat Nov 14, 2020 12:09 pm
Forum: Lewis Structures
Topic: Polyatomic Ions
Replies: 2
Views: 15

Polyatomic Ions

Do we have to memorize polyatomic ions for the midterm?
by Alessia Renna 1D
Sun Nov 08, 2020 11:13 am
Forum: Trends in The Periodic Table
Topic: Sapling Question (Radius)
Replies: 10
Views: 68

Re: Sapling Question (Radius)

Cs+ is a cation, meaning it loses an electron. Therefore, it will decrease in size and be the smallest of the 3. Cs- is an anion, meaning it gains an electron. Because of this, it will increase in size and be the largest of the 3. Thus, Cs is in the middle of the two.
by Alessia Renna 1D
Sun Nov 08, 2020 11:00 am
Forum: Trends in The Periodic Table
Topic: Ionization Energy
Replies: 9
Views: 40

Re: Ionization Energy

ionization energy is the quantity of energy that must be absorbed in order to eject an electron, thus forming a cation. So, as an electron increases in size, and thus number of shells, the electrons in the outer shells are not as tightly kept, meaning that it requires less energy to remove them.
by Alessia Renna 1D
Fri Nov 06, 2020 7:24 pm
Forum: Quantum Numbers and The H-Atom
Topic: order of electron cnfiguration
Replies: 13
Views: 122

Re: order of electron cnfiguration

the 3d orbital has a lower energy than the 4s orbital
by Alessia Renna 1D
Fri Nov 06, 2020 7:17 pm
Forum: Trends in The Periodic Table
Topic: Nuclear Charge
Replies: 7
Views: 39

Re: Nuclear Charge

Nuclear charge is the charge of the nucleus (which is determined by proton and electron numbers)
by Alessia Renna 1D
Fri Nov 06, 2020 7:16 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Removing Electrons from orbitals
Replies: 4
Views: 49

Re: Removing Electrons from orbitals

If an electron is removed to create a +1 ion (cation), it would be a valence electron (highest energy orbital).
by Alessia Renna 1D
Sat Oct 31, 2020 4:44 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Sapling Homework
Replies: 8
Views: 57

Sapling Homework

I an having trouble inputting the electron configuration into my sapling answers. For the question that asks you to find the electron configuration for S, I have tried to input my answer many times ([Ne] 3s^2,3p^4) but it keeps telling me I am incorrect. I know my answer is correct so it must be the...
by Alessia Renna 1D
Sat Oct 31, 2020 9:59 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Change in Velocity Uncertainty
Replies: 4
Views: 67

Re: Change in Velocity Uncertainty

Because it says +/- you would multiply by two, making the uncertainty in velocity 0.2m/s. You would then multiply this by the mass given in the problem to get delta P. You can then plug that delta P value into the uncertainty equation (given to you on the constants and equations sheet) in order to f...
by Alessia Renna 1D
Sat Oct 31, 2020 9:56 am
Forum: Molarity, Solutions, Dilutions
Topic: Fundamentals G21
Replies: 3
Views: 50

Re: Fundamentals G21

The volume would be the 500 mL of water, usually volume in dilution equations will be in L or mL
by Alessia Renna 1D
Fri Oct 30, 2020 3:32 pm
Forum: Empirical & Molecular Formulas
Topic: Mass Percent Composition
Replies: 3
Views: 66

Re: Mass Percent Composition

If you are given the grams of each element in the compound, you should find the percent mass composition first and then convert to grams (assuming a total of 100 g) and then convert to moles!
by Alessia Renna 1D
Fri Oct 30, 2020 3:29 pm
Forum: Properties of Light
Topic: photons vs quanta
Replies: 3
Views: 61

Re: photons vs quanta

Quanta are like units --> they are the smallest unit/particle of something. Photons are the smallest unit/particles of light so technically they are quanta of light. :)
by Alessia Renna 1D
Mon Oct 26, 2020 3:34 pm
Forum: SI Units, Unit Conversions
Topic: Dimensional Analysis
Replies: 7
Views: 72

Dimensional Analysis

Can someone please explain dimensional analysis?
by Alessia Renna 1D
Wed Oct 21, 2020 8:05 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Worked Example from Wednesday (10/21) lecture
Replies: 3
Views: 48

Worked Example from Wednesday (10/21) lecture

In the lecture today, when he is finding the uncertainty of the velocity in his first example with the incorrect H-atom, how does he know that the mass of the electron is 9.1 x 10^-31 kg? This is timestamp 26:03 in Lecture #9.
by Alessia Renna 1D
Wed Oct 21, 2020 11:56 am
Forum: DeBroglie Equation
Topic: Rearranging De Broglie Equation
Replies: 17
Views: 118

Rearranging De Broglie Equation

How would you rearrange the De Broglie Equation in order to calculate velocity using wavelength, mass, and planck's constant?
by Alessia Renna 1D
Wed Oct 21, 2020 10:50 am
Forum: DeBroglie Equation
Topic: Measureable-wavelike properties
Replies: 5
Views: 68

Re: Measureable-wavelike properties

The smallest detectable power for wavelike properties is 10^-15 m. Anything larger will act as a classical object.
by Alessia Renna 1D
Tue Oct 20, 2020 11:45 am
Forum: Properties of Electrons
Topic: Lyman vs. Balmer series
Replies: 20
Views: 180

Re: Lyman vs. Balmer series

The Lyman series corresponds to any transition that ends at the ground state or n =1, meaning it falls in the ultraviolet region. The Balmer series corresponds to any transition that ends at n = 2, meaning it falls in the visible region
by Alessia Renna 1D
Tue Oct 20, 2020 11:40 am
Forum: Properties of Electrons
Topic: Bound vs Free
Replies: 4
Views: 35

Bound vs Free

This is a very basic question probably from high school chem but what is the difference between a bound and free electron?
by Alessia Renna 1D
Fri Oct 16, 2020 2:34 pm
Forum: SI Units, Unit Conversions
Topic: 10^?
Replies: 2
Views: 62

10^?

Silly question: when you are doing calculations, how do you know what power 10 goes to in the answer? For example:

(6.6.36 x 10^ -34 Js)*(3 x 10^8 m.s)/(3.61 x 10^-19) = 5.51 x 10^-9 m

How would I know/calculate that the answer includes 10^-9?

Thanks! :)
by Alessia Renna 1D
Thu Oct 15, 2020 11:58 am
Forum: Properties of Light
Topic: Worked Example from Wednesday lecture
Replies: 3
Views: 54

Worked Example from Wednesday lecture

Can someone please explain this example: if 3.61 x 10^-19 J is required to remove an electron with zero kinetic energy from a metal surface, what would be the longest wavelength light that could do this? I understand the equations and rearranging of them but I am having a hard time understanding the...
by Alessia Renna 1D
Wed Oct 14, 2020 6:09 pm
Forum: Properties of Light
Topic: photons and quanta
Replies: 7
Views: 83

Re: photons and quanta

A quanta is the smallest particle of something, that something in this case is light, of which a photon is the smallest possible particle.
by Alessia Renna 1D
Wed Oct 14, 2020 6:06 pm
Forum: Properties of Light
Topic: Relationship between energy of photon and energy to remove
Replies: 5
Views: 44

Relationship between energy of photon and energy to remove

The energy of the photon is supposed to be equal to or greater than the energy required to remove an electron, correct? I keep getting confused with this. If it is not greater than or equal to, does that then mean that the electron cannot be removed no matter what?
by Alessia Renna 1D
Wed Oct 14, 2020 1:52 pm
Forum: Properties of Light
Topic: Photons
Replies: 4
Views: 47

Photons

Are photons just defined as the "packets of energy" that make up light? What does it mean that photons are a "quantum of light"?
by Alessia Renna 1D
Sat Oct 10, 2020 10:57 am
Forum: Significant Figures
Topic: How to deal with significant figures in decimals with zeros.
Replies: 20
Views: 200

Re: How to deal with significant figures in decimals with zeros.

Zeros that are in between integers are significant! In your example there would be 4 significant figures.
by Alessia Renna 1D
Thu Oct 08, 2020 6:08 pm
Forum: SI Units, Unit Conversions
Topic: Kg to g
Replies: 13
Views: 152

Kg to g

Simple question but how do you calculate Kg to g and vice versa by hand?
by Alessia Renna 1D
Wed Oct 07, 2020 1:46 pm
Forum: Balancing Chemical Reactions
Topic: Law of Conservation?
Replies: 16
Views: 152

Re: Law of Conservation?

The law of conservation states that the mass of the reactants will always equal the mass of the products. The moles of each compound can change as long as the moles of each element are preserved.
by Alessia Renna 1D
Tue Oct 06, 2020 10:11 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Equations --> #18 in Module
Replies: 4
Views: 77

Balancing Equations --> #18 in Module

When a question says that an element (i.e. Butan Gas) is combusted, do we automatically assume that the reactant half of the equation would be the element + 02(g) ? So in this case it would be C4H10(g) + 02(g)?
by Alessia Renna 1D
Tue Oct 06, 2020 8:57 pm
Forum: Empirical & Molecular Formulas
Topic: Sapling HW 9
Replies: 21
Views: 227

Re: Sapling HW 9

Yes because you must have whole atoms, the empirical formula is the ratio of moles

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