Search found 31 matches

by Odalys Cuevas 1C
Sun Jun 10, 2018 11:26 pm
Forum: Conjugate Acids & Bases
Topic: Conjugate Acids/Bases
Replies: 8
Views: 399

Re: Conjugate Acids/Bases

What I heard was that a conjugate acid is when a proton is added (H+) and the conjugate base is when the proton is taken away (H+). for example: HCl + H2O--->H3O(+) + Cl(-) - the HCl is the acid and Cl is the conjugate base since the H was taken away - H2O is the base and the H3O is the conjugate ac...
by Odalys Cuevas 1C
Wed Jun 06, 2018 9:08 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular Shapes On the Final
Replies: 3
Views: 128

Re: Molecular Shapes On the Final

I think that we might be asked about the hybridization of the molecular shapes since we went over them in lecture. I attached a picture of the notes i took which can be helpful.
by Odalys Cuevas 1C
Wed Jun 06, 2018 8:25 pm
Forum: Lewis Structures
Topic: Lowest energy lewis structure
Replies: 5
Views: 1316

Lowest energy lewis structure

Can someone explain how to determine the lowest energy Lewis structure of a molecule and maybe provide an example.
by Odalys Cuevas 1C
Wed Jun 06, 2018 8:08 pm
Forum: Lewis Structures
Topic: Drawing Lewis Structures on the Final Exam
Replies: 5
Views: 236

Re: Drawing Lewis Structures on the Final Exam

I remember hearing that you don't have to be exactly accurate when drawing them since it can get tricky, but you should know what the angles are for the shapes in the VSEPR structure if you are asked for them. For example for AX3 its trigonal planar and has bond angles of 120.
by Odalys Cuevas 1C
Sun Jun 03, 2018 2:37 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Tetrahedral and Square planar
Replies: 8
Views: 417

Re: Tetrahedral and Square planar

Also I have in my notes that a tetrahedral has bond angles of about 109.5 degrees and square planar 90 degree bond angles.
by Odalys Cuevas 1C
Sun Jun 03, 2018 2:15 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angles [ENDORSED]
Replies: 3
Views: 136

Re: Bond angles [ENDORSED]

I find that by knowing the strengths of repulsions (Lone pair & lone pair > Lone pair & bonding pair > bonding pair & bonding pair) is helpful to understand that there will be more repulsion if there are lone pairs therefore causing the angles to become smaller around.
by Odalys Cuevas 1C
Sun Jun 03, 2018 2:04 pm
Forum: Hybridization
Topic: Hybridization
Replies: 3
Views: 133

Hybridization

I am having trouble with this topic. Can someone explain what hybridization is and how to determine it? Also what does it mean to be unhybridized?

Thank you
by Odalys Cuevas 1C
Sat May 26, 2018 11:51 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR
Replies: 3
Views: 140

VSEPR

Can molecules have the same VSEPR formula and what would that mean for the shape, the name and the electron arrangement? Also, what is an example of this if there is one?
by Odalys Cuevas 1C
Sat May 26, 2018 11:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Remembering Bond Angles
Replies: 4
Views: 186

Re: Remembering Bond Angles

Do we also need to know the name of the bonds and the name of the shape they make?
by Odalys Cuevas 1C
Sat May 26, 2018 11:25 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizing power
Replies: 10
Views: 544

Re: Polarizing power

Im having trouble understanding this topic so I was wondering if anyone can explain the difference between polarizing power and polarizability and provide a quick example.
by Odalys Cuevas 1C
Sat May 19, 2018 9:21 pm
Forum: Lewis Structures
Topic: HW 3.37
Replies: 2
Views: 114

Re: HW 3.37

The way that I did this was that I counted the total number of electrons on the whole structure (32 electrons) then I saw which elements were given and then counted the amount of valence electron each element had and multiplied it by the number there was on the structure (3 * 7 for Cl and 1 * 6 for ...
by Odalys Cuevas 1C
Sat May 19, 2018 8:53 pm
Forum: Resonance Structures
Topic: Resonance Structures
Replies: 9
Views: 425

Re: Resonance Structures

I believe that for resonance structures the formal charge may be different and when choosing which is the better structure you choose the one with the lowest formal charge or closest that adds to zero.
by Odalys Cuevas 1C
Sat May 19, 2018 8:29 pm
Forum: Ionic & Covalent Bonds
Topic: Radicals [ENDORSED]
Replies: 5
Views: 206

Re: Radicals [ENDORSED]

Radicals are atoms with unpaired valence electrons and usually have an odd number of electrons.
by Odalys Cuevas 1C
Sun May 13, 2018 5:21 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent Bonds
Replies: 4
Views: 164

Re: Covalent Bonds

I think that we choose an atom with the lowest ionization energy as the central atom because those are the atoms that have electrons that are less tight.It makes it easier to add more electrons to the atoms to make it less likely to remove electrons and have more bonds.
by Odalys Cuevas 1C
Sun May 13, 2018 4:02 pm
Forum: Lewis Structures
Topic: Most Important Lewis Structure
Replies: 4
Views: 163

Re: Most Important Lewis Structure

I think that you should also first you would see which would fulfill the octet rule, then see which has the smallest formal charge and then see where there is more electronegativity to make that lewis structure the most important one.
by Odalys Cuevas 1C
Sun May 13, 2018 3:50 pm
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 4
Views: 168

Re: Lewis Structures

I think whats most important is that you have the atom that is the least electronegative in the middle because this way you can just add more atoms to fulfill the octet rule.
by Odalys Cuevas 1C
Sun May 06, 2018 2:47 pm
Forum: Ionic & Covalent Bonds
Topic: cation vs anion
Replies: 14
Views: 459

Re: cation vs anion

Another way is that Cations have a "t" which is similar to a plus sign so its an easy way to know its a positive charge. And anions are just the opposite. Also when you loose electrons, you have a positive charge and when you gain electrons you have negative charge.
by Odalys Cuevas 1C
Sun May 06, 2018 2:00 pm
Forum: Photoelectric Effect
Topic: Test #2 Question 7 [ENDORSED]
Replies: 2
Views: 184

Test #2 Question 7 [ENDORSED]

Copper is used widely in electrical wiring due to its high electrical conductivity and malleability. The threshold energy or "work function" of the copper atom is 7.52* 10^-19 J. What is the maximum wavelength of light (lowest energy) you need to shine onto the copper metal in vacuum to ej...
by Odalys Cuevas 1C
Sun May 06, 2018 12:31 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Switching 3d and 4s
Replies: 6
Views: 300

Re: Switching 3d and 4s

Just to clarify, this means that for any element with an electron configuration that has both s and d orbitals, the d orbital would come before the s and followed by p. But for elements without the d orbital it would be the s orbital first. Correct me if I am wrong. And also s orbitals have higher e...
by Odalys Cuevas 1C
Sun Apr 29, 2018 10:38 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: PROBLEM 2.1
Replies: 4
Views: 149

Re: PROBLEM 2.1

Also the higher the number (n), the further away the electrons are from the nucleus so those electrons have higher energy compared to electrons closer to the nucleus.
by Odalys Cuevas 1C
Sun Apr 29, 2018 10:20 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: PROBLEM 2.21
Replies: 2
Views: 104

Re: PROBLEM 2.21

For principal it is just the n value, so you would look at the row number on the periodic table or in this case just the number given. Then for the angular its the l values (0,1,2,3) and they correspond to the s,p,d,f orbitals.
by Odalys Cuevas 1C
Sun Apr 29, 2018 10:04 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Difference between a shell, subshell, and orbital
Replies: 4
Views: 258

Re: Difference between a shell, subshell, and orbital

Do the subshells (s, p, d, and f) correspond to the orbital angular momentum quantum numbers ( l =0, 1, 2, 3)? I think that each subshell does correspond to the orbital angular momentum quantum numbers. For example, s would correspond to 0, p to 1 and so on. It's an effective way to know from what ...
by Odalys Cuevas 1C
Sat Apr 21, 2018 5:23 pm
Forum: Limiting Reactant Calculations
Topic: Question from test 1 [ENDORSED]
Replies: 4
Views: 317

Re: Question from test 1 [ENDORSED]

I think that to do the second part you would take the mol you got from part a that allowed you to determine that 02 was the limiting reagent and turn that to grams of H2. Then you would subtract the grams given by the grams you found to get what is left over of the unreacted one. Thats how we did it...
by Odalys Cuevas 1C
Sat Apr 21, 2018 5:02 pm
Forum: Properties of Light
Topic: still don't uderrsatnd what a photon is [ENDORSED]
Replies: 20
Views: 411

Re: still don't uderrsatnd what a photon is [ENDORSED]

Photons don't have mass but they do have energy and momentum, so they are able to move with the speed of light.
by Odalys Cuevas 1C
Sat Apr 21, 2018 4:27 pm
Forum: Properties of Light
Topic: test 2
Replies: 18
Views: 589

Re: test 2

Since some questions might be asking our understanding of topics would that be like knowing where equations come from and what they mean? Or what are some examples of the type of questions that can be asked?
by Odalys Cuevas 1C
Sun Apr 15, 2018 9:23 pm
Forum: SI Units, Unit Conversions
Topic: writing out conversions in one long line vs. steps
Replies: 16
Views: 613

Re: writing out conversions in one long line vs. steps

I usually find doing them in one long line more helpful because you can cancel easier and also if you seem to have made a mistake you can catch it quicker since it is all in one line. Its just quicker and more helpful during timed exams.
by Odalys Cuevas 1C
Sun Apr 15, 2018 9:15 pm
Forum: Empirical & Molecular Formulas
Topic: Finding Empirical and Molecular Formula [ENDORSED]
Replies: 6
Views: 385

Re: Finding Empirical and Molecular Formula [ENDORSED]

If there are 2 lines showing a bond do you have to add 2 to both of the elements? Also should you look at the lines or at the number of elements?
by Odalys Cuevas 1C
Sun Apr 15, 2018 9:07 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Chemical Reactions
Replies: 5
Views: 248

Re: Balancing Chemical Reactions

What works for me is to draw a vertical line in the arrow and then on each side write down each of the elements with the number each has. Then I see which one shows up less on one side and more on the other and balance those. Then I see which ones are left to balance and go for what of the products ...
by Odalys Cuevas 1C
Sun Apr 15, 2018 8:13 pm
Forum: Empirical & Molecular Formulas
Topic: Finding Molecular X
Replies: 9
Views: 340

Re: Finding Molecular X

Do you mean when you are just given the name? For example Nitrogen trifluoride so then you have to figure out what that compound is.
by Odalys Cuevas 1C
Sat Apr 07, 2018 10:19 pm
Forum: Empirical & Molecular Formulas
Topic: Finding the molecular formula [ENDORSED]
Replies: 5
Views: 201

Re: Finding the molecular formula [ENDORSED]

To find the molecular formula, you would need the molar mass of the empirical formula and most likely the molar mass of the molecular formula will be given. So all you do is divide the molar mass of the molecular formula by the molar mass of the empirical formula and you will get your answer needed ...
by Odalys Cuevas 1C
Sat Apr 07, 2018 9:53 pm
Forum: General Science Questions
Topic: Rusty on High School Chem [ENDORSED]
Replies: 165
Views: 100732

Re: Rusty on High School Chem [ENDORSED]

Since there is no longer a course reader, where would one suggest to find more practice problems to prepare for the first test? The module questions are helpful, but they are different than both the homework problems and the problems received in discussion section. Hey, there are worksheets that th...

Go to advanced search