So in general a weak base will raise the pH and a weak acid will lower the pH, right?
Yes, remember that acidic solutions have lower pH (so on the left side of the scale), while more basic solutions have higher pH (right side of the scale).
Search found 50 matches
- Sun Dec 06, 2020 2:58 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: weak acid/base and pH
- Replies: 9
- Views: 780
- Sun Dec 06, 2020 2:54 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 3
- Views: 229
Final
Does anyone know how many questions there will be in the final? and if the latest material will be covered the most, or if all the material will be equally distributed in the exam?
- Sun Dec 06, 2020 2:51 pm
- Forum: Student Social/Study Group
- Topic: Studying for Final Exam
- Replies: 57
- Views: 2904
Re: Studying for Final Exam
I would recommend first going over your notes, highlighting the most important concepts and formula. After you have reviewed the material, I would recommend doing as much practice problems as possible. You can do the problems assigned in the textbook as Dr. Lavelle has said that some of them may be ...
- Sun Dec 06, 2020 2:48 pm
- Forum: Air Pollution & Acid Rain
- Topic: Formation of Acid Rain
- Replies: 5
- Views: 687
Re: Formation of Acid Rain
Acid rain is a very dangerous phenomenon that occurs through chemical reactions occurring in the atmosphere. When chemicals such as Carbon Dioxide (CO2), S02 and NO2 elevate in the atmosphere they react with water vapor and form acid rain. Water usually is neutral, being acid, it has a corrosive eff...
- Sun Dec 06, 2020 2:44 pm
- Forum: Lewis Acids & Bases
- Topic: Acids vs Basis
- Replies: 11
- Views: 677
Acids vs Basis
What are the main differences we should be looking for when recognizing acids or basis, looking at their formula and structure?
- Sun Dec 06, 2020 2:41 pm
- Forum: Naming
- Topic: Naming Coordination Compounds
- Replies: 5
- Views: 288
Naming Coordination Compounds
Does anyone have any helpful tips for remembering the rules when naming coordination compounds?
- Sun Nov 29, 2020 1:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: sapling #12
- Replies: 13
- Views: 833
Re: sapling #12
Emilie_Paltrinieri_1K wrote:I am getting an error, is this structure not correct?
I just realized I was missing a lone pair on the O!!
- Sun Nov 29, 2020 1:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Delocalized pi bond
- Replies: 4
- Views: 178
Delocalized pi bond
How can we determine whether a pi bond is delocalized? What does it mean?
- Sun Nov 29, 2020 12:55 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: sapling #12
- Replies: 13
- Views: 833
Re: sapling #12
I am getting an error, is this structure not correct?
- Sun Nov 29, 2020 12:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Uploading Screenshot
- Replies: 1
- Views: 124
Uploading Screenshot
Hi! I am having trouble uploading a screenshot in one of these texts. I tried both dragging the image in the message box and uploading it as a file, but nothing appears in the chat. Does anyone know how to help me?
- Sun Nov 29, 2020 12:28 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Polarity
- Replies: 16
- Views: 800
Polarity
Is a molecule that has a lone pair polar?
- Sun Nov 22, 2020 11:58 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lecture 20 VSEPR
- Replies: 6
- Views: 352
Re: Lecture 20 VSEPR
So is there a general rule to guide us in choosing a specific Lewis Structure for every molecule?
- Sun Nov 22, 2020 11:55 am
- Forum: Student Social/Study Group
- Topic: Finals!
- Replies: 43
- Views: 2088
Re: Finals!
Yes it's cumulative, so everything starting from the beginning of the quarter!
- Sun Nov 22, 2020 8:44 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lecture 20 VSEPR
- Replies: 6
- Views: 352
Lecture 20 VSEPR
I had a question regarding the VESPR model for Sulfite Ion, S03^2-. As Dr. Lavelle said, the lewis structure of the ion wasn't the most stable as it had a lone pair. The lone pair has then affected the angle at which the atoms lie, as they repel the bonding e- pairs more. However, if we would have d...
- Thu Nov 19, 2020 9:50 am
- Forum: Lewis Structures
- Topic: Textbook 2B.1
- Replies: 4
- Views: 268
Re: Textbook 2B.1
But a double bond would result in the same Formal charge of a single bond.
Fluorine: 7e-
Fc double bond= 7-(5+(4/2))=0
Fc single bond= 7-(6+(2/2))=0
Fluorine: 7e-
Fc double bond= 7-(5+(4/2))=0
Fc single bond= 7-(6+(2/2))=0
- Thu Nov 19, 2020 9:25 am
- Forum: Lewis Structures
- Topic: Textbook 2B.1
- Replies: 4
- Views: 268
Textbook 2B.1
This exercise is asking to draw the Lewis Structures of various molecules.
I was wondering why in the structure of ONF and NF2 we don't draw double bonds to pair all of the lone e- pairs that N has, but rather they keep a pair of loose e- on the N?
I was wondering why in the structure of ONF and NF2 we don't draw double bonds to pair all of the lone e- pairs that N has, but rather they keep a pair of loose e- on the N?
- Thu Nov 19, 2020 7:43 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Textbook Exercise 2A.17
- Replies: 1
- Views: 159
Textbook Exercise 2A.17
This exercise asks to predict the number of valence electrons for various ions.
For example, the ion Mn^4+, in the solutions manual has 3 valence e-.
Since valence e- are the ones in the outermost shell, shouldn't' the solution exclude the e- in 4s and just =1?
For example, the ion Mn^4+, in the solutions manual has 3 valence e-.
Since valence e- are the ones in the outermost shell, shouldn't' the solution exclude the e- in 4s and just =1?
- Sun Nov 15, 2020 3:39 pm
- Forum: Coordinate Covalent Bonds
- Topic: Just to clear it up
- Replies: 16
- Views: 1050
Re: Just to clear it up
Yes, Lewis bases which are usually anions (who can therefore donate electrons) create coordinate covalent bonds when attached to the acid.
- Sun Nov 15, 2020 3:34 pm
- Forum: Dipole Moments
- Topic: London (dispersion) forces
- Replies: 4
- Views: 315
London (dispersion) forces
How can I determine if a molecule exhibits ONLY London (dispersion) forces?
- Sun Nov 15, 2020 3:30 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling week 5-6 question 9
- Replies: 1
- Views: 105
Sapling week 5-6 question 9
I can't seem to find the correct answer for question 9, which is asking which lewis structures are best based on formal charge.
Could someone tell what steps I should follow to come to the right solution please?
Could someone tell what steps I should follow to come to the right solution please?
- Sun Nov 15, 2020 3:25 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formula Charge Simplified Formula
- Replies: 2
- Views: 204
Formula Charge Simplified Formula
I know there is a simple formula to find the Formula Charge of an atom, but I don't remember what it was. Could someone write it down for me?
- Sun Nov 15, 2020 2:34 pm
- Forum: Bond Lengths & Energies
- Topic: Sapling week 5-6 question 4
- Replies: 1
- Views: 93
Sapling week 5-6 question 4
What does it mean to have "ample" and "overwhelmingly" when talking about bonds in chemistry?
- Mon Nov 09, 2020 2:39 am
- Forum: Electronegativity
- Topic: Confusion between electronegativity and electron affinity
- Replies: 15
- Views: 821
Re: Confusion between electronegativity and electron affinity
They are actually two different things.
Electronegativity describes how well an atom can attract electrons towards it.
Electron affinity represents the amount of energy released when an electron has been added to a atom/molecule, making it a negative ion.
Electronegativity describes how well an atom can attract electrons towards it.
Electron affinity represents the amount of energy released when an electron has been added to a atom/molecule, making it a negative ion.
- Mon Nov 09, 2020 2:35 am
- Forum: Resonance Structures
- Topic: Lewis Structure
- Replies: 5
- Views: 510
Re: Lewis Structure
These are the key steps when determining the lewis structure. Step 1: Determine the total number of valence electrons. Step 2: Write the skeleton structure of the molecule. Step 3: Use two valence electrons to form each bond in the skeleton structure. Step 4: Try to satisfy the octets of the atoms b...
- Mon Nov 09, 2020 2:31 am
- Forum: Resonance Structures
- Topic: structure of lower energy
- Replies: 5
- Views: 290
Re: structure of lower energy
Yes, you have identify which of the lewis structures in the picture has the lowest energy configuration. So consider the overall charge of the different structures
- Sun Nov 08, 2020 1:07 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Solutions
- Replies: 4
- Views: 230
Midterm Solutions
I was wondering whether we are able to view the solutions of the midterm in order to go over it?
- Sun Nov 08, 2020 1:01 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Grading
- Replies: 6
- Views: 327
Chemistry Community Grading
Could someone tell me what the grading scale for Chemistry Community is? (Number of points, if it's on a weekly basis, ecc)
- Mon Nov 02, 2020 12:24 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration
- Replies: 8
- Views: 386
Re: Electron Configuration
4s comes before 3d, remember what the Aufbau Principle states!
- Sun Nov 01, 2020 4:55 am
- Forum: Administrative Questions and Class Announcements
- Topic: Offline Lecture Content
- Replies: 4
- Views: 366
Offline Lecture Content
Does anyone know if there is a way to make the lectures available to view offline? Thank you so much!
- Sun Oct 25, 2020 10:42 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Electron Density Distribution
- Replies: 8
- Views: 422
Re: Electron Density Distribution
Do we need to be able to find the electron density or is it something that will be given in the problems?
- Sun Oct 25, 2020 10:40 am
- Forum: DeBroglie Equation
- Topic: Derivation of Equations on Midterm?
- Replies: 17
- Views: 612
Derivation of Equations on Midterm?
Hi! I was wondering whether we will have to be able to show the derivation of the equations we have studied, in particular of the De Broglie equation, in the midterm?
- Sun Oct 25, 2020 10:34 am
- Forum: Photoelectric Effect
- Topic: Intensity vs. Frequency
- Replies: 22
- Views: 1918
Re: Intensity vs. Frequency
So what was the new equation that they found after doing the experiment of the photoelectric effect?
- Sun Oct 25, 2020 10:27 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Advice for studying
- Replies: 92
- Views: 7824
Re: Advice for studying
I would recommend watching the lectures and looking at the solved examples on the textbook to see how the problems function. After that, do the homework and ask for help if you don't understand some of the exercises!
- Sun Oct 25, 2020 10:23 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers
- Replies: 3
- Views: 217
Quantum Numbers
Could someone please explain what are the values that quantum numbers can have in relation to one another? I haven't clearly understood what Lavelle explained during lecture regarding the value that each quantum number can have (ex. l=n-1, ecc)
- Sun Oct 25, 2020 10:21 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Lecture confusion in quantum numbers
- Replies: 6
- Views: 246
Re: Lecture confusion in quantum numbers
What does a 2px state represent?
- Sun Oct 18, 2020 3:33 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Where can I buy a webcam for a reasonable price?
- Replies: 60
- Views: 3913
Re: Where can I buy a webcam for a reasonable price?
You can also use a second device you have! That would avoid spending extra money.
- Sun Oct 18, 2020 3:30 pm
- Forum: Limiting Reactant Calculations
- Topic: Exam Material
- Replies: 2
- Views: 202
Exam Material
Hi! So for the midterm will we just need our laptop and an external camera? Is there something else we need (calculator, ecc)? or will it be provided in the respondus software
- Sun Oct 18, 2020 3:28 pm
- Forum: Balancing Chemical Reactions
- Topic: Mixed Numbers
- Replies: 7
- Views: 357
Re: Mixed Numbers
You should use whatever numbers is necessary to balance the equation and if in the end you have a fraction, you can multiply both sides by a different number so that the fraction becomes an integer.
- Sun Oct 18, 2020 3:25 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Accessing the E-textbook [ENDORSED]
- Replies: 125
- Views: 33443
Re: Accessing the E-textbook [ENDORSED]
I don't think sapling is mandatory, but I would recommend it as it is a great resource, as it gives another explanation of the material covered in class.
- Sun Oct 18, 2020 3:22 pm
- Forum: SI Units, Unit Conversions
- Topic: Metric Conversions
- Replies: 9
- Views: 1784
Re: Metric Conversions
"King Henry Doesn't Usually Drink Chocolate Milk"
- Sun Oct 18, 2020 3:19 pm
- Forum: SI Units, Unit Conversions
- Topic: Midterm
- Replies: 26
- Views: 1231
Midterm
Does anyone know how the midterm exam will be structured? Like how many questions there will be and if the questions will all be exercises or if there can be some theory questions as well?
- Sun Oct 18, 2020 10:17 am
- Forum: Einstein Equation
- Topic: m vs nm
- Replies: 66
- Views: 3790
Re: m vs nm
I think that if the question doesn't specify particular units of measurement, then both should be fine as they have equal values. Just remember to use the correct scientific notation nm= 10^-9
Also, round to the correct significant figures to not have any inconsistencies!
Also, round to the correct significant figures to not have any inconsistencies!
- Sun Oct 11, 2020 7:35 am
- Forum: Limiting Reactant Calculations
- Topic: Actual yield
- Replies: 20
- Views: 914
Re: Actual yield
You can calculate the theoretical yield in problems as it is the value with the optimal efficiency of the experiment. But, in some cases, the actual yield doesn't match the theoretical yield as, for example, some solution can stick to the beaker.
- Sun Oct 11, 2020 7:33 am
- Forum: Administrative Questions and Class Announcements
- Topic: Homework
- Replies: 6
- Views: 329
Homework
Hi, I was just wondering whether the Post-assessment of the Audio Visual is graded and counts as HW or if just Sapling does?
- Sun Oct 11, 2020 7:15 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Calculating number of moles of an element
- Replies: 10
- Views: 497
Calculating number of moles of an element
When calculating the number of moles of an element we always use 100g. I was wondering if we use 100g just for semplicity, and if there is any particular case where we should consider different quantities.
- Sun Oct 11, 2020 7:03 am
- Forum: Significant Figures
- Topic: All students read this sig fig post [ENDORSED]
- Replies: 170
- Views: 35425
Re: All students read this sig fig post [ENDORSED]
I think we will have to understand, through the various rules, what significant figure is appropriate for the exercise given. Remember the different regarding zeros, decimal places and different approaches for subtraction/addition and multiplication/division.
- Sun Oct 11, 2020 7:00 am
- Forum: Balancing Chemical Reactions
- Topic: Periodic Table
- Replies: 66
- Views: 5034
Re: Periodic Table
I think the periodic table would be provided. I would recommend becoming familiar with all the information given in the table. For example, atomic mass, type of element, ecc
- Thu Oct 08, 2020 9:01 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Sapling HW Question 6
- Replies: 4
- Views: 202
Sapling HW Question 6
Hi, I am having trouble with question 6 of the week 1 homework.
This is what I did:
1) I calculated the molar mass of CuNO3= 63.546+14.001+3*(15.9994)=125.56g/mol
2) calculated the # of moles: 5.68/125.56= 0.045 mol
3) M=n/V--> V=n/M
V=0.045mol/0.440M=0.1L
V=100mL
Could someone please help me
This is what I did:
1) I calculated the molar mass of CuNO3= 63.546+14.001+3*(15.9994)=125.56g/mol
2) calculated the # of moles: 5.68/125.56= 0.045 mol
3) M=n/V--> V=n/M
V=0.045mol/0.440M=0.1L
V=100mL
Could someone please help me
- Thu Oct 08, 2020 8:00 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Sapling HW Question 5
- Replies: 10
- Views: 427
Re: Sapling HW Question 5
Try rounding to 2 sig figs so that you won't have any decimal places, but just integers
- Wed Oct 07, 2020 1:45 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Students in different time zones [ENDORSED]
- Replies: 27
- Views: 2393