Search found 50 matches
- Sat Dec 07, 2019 5:41 pm
- Forum: Naming
- Topic: bis-,tris-,tetrakis-
- Replies: 2
- Views: 188
bis-,tris-,tetrakis-
When do we use the prefixes bis-, tris-, tetrakis- instead of bi-, tri-, tetra and why?
- Sat Dec 07, 2019 5:40 pm
- Forum: Biological Examples
- Topic: Porphyrin
- Replies: 1
- Views: 191
Porphyrin
What does porphyrin mean?
- Sat Dec 07, 2019 5:39 pm
- Forum: Biological Examples
- Topic: Hemoglobin
- Replies: 4
- Views: 344
Hemoglobin
How is hemoglobin made?
- Sat Dec 07, 2019 5:35 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric vs Amphiprotic
- Replies: 13
- Views: 1434
Amphoteric vs Amphiprotic
What is the difference between an amphoteric and amphiprotic molecule?
- Sat Dec 07, 2019 5:31 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Nonmetal oxides
- Replies: 2
- Views: 244
Nonmetal oxides
Why do nonmetal oxides not dissociate in the presence of water?
- Sun Dec 01, 2019 2:39 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Acid Strength
- Replies: 3
- Views: 220
Acid Strength
Why does increasing the number of oxygen atoms make the acid stronger?
- Sun Dec 01, 2019 2:36 am
- Forum: Biological Examples
- Topic: Cisplatin vs Transplatin
- Replies: 2
- Views: 224
Cisplatin vs Transplatin
Why is cisplatin used to treat cancer but not transplatin?
- Sun Dec 01, 2019 2:35 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Shape
- Replies: 1
- Views: 146
Shape
What is the shape of a coordination compound that has 3 ligands?
- Sun Dec 01, 2019 2:34 am
- Forum: Conjugate Acids & Bases
- Topic: Strength of Conjugate Acids and Bases
- Replies: 3
- Views: 231
Strength of Conjugate Acids and Bases
Why are conjugate bases of strong acids weak?
- Sun Dec 01, 2019 2:33 am
- Forum: Lewis Acids & Bases
- Topic: Lewis vs Bronsted
- Replies: 4
- Views: 294
Lewis vs Bronsted
Is it possible for an element or molecule to be a Lewis acid or base but not a Bronsted acid or base?
- Sat Nov 23, 2019 10:35 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Acids
- Replies: 13
- Views: 1515
Acids
What acids are we expected to know?
- Sat Nov 23, 2019 10:34 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligand
- Replies: 3
- Views: 238
Ligand
What is a ligand?
- Sat Nov 23, 2019 10:33 pm
- Forum: Biological Examples
- Topic: Biological Importance
- Replies: 6
- Views: 358
Biological Importance
What elements/molecules are we expected to know the biological importance/function of?
- Sat Nov 23, 2019 10:32 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation Number
- Replies: 3
- Views: 282
Oxidation Number
How do we determine oxidation number?
Prefixes
When do we use the prefixes, bis, tris, tetrakis, pentakis?
- Thu Nov 14, 2019 11:04 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electrons
- Replies: 9
- Views: 433
Electrons
How does spreading electrons further apart make the molecule more stable?
- Thu Nov 14, 2019 10:58 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Repulsion
- Replies: 1
- Views: 161
Repulsion
Why do lone pairs have more repulsion power than bond pairs?
- Thu Nov 14, 2019 10:56 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Arrangement vs Shape
- Replies: 3
- Views: 178
Arrangement vs Shape
What is the difference between the arrangement and shape of a molecule?
- Thu Nov 14, 2019 10:56 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Formula
- Replies: 3
- Views: 168
VSEPR Formula
How do you determine VSEPR formula?
- Thu Nov 14, 2019 10:55 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle
- Replies: 9
- Views: 503
Bond Angle
Why is the bond angle of a trigonal pyramidal a little less than 109.5 degrees instead of being exactly 109.5 degrees?
- Thu Nov 07, 2019 1:09 pm
- Forum: Coordinate Covalent Bonds
- Topic: Elements that can form coordinate covalent bonds
- Replies: 2
- Views: 243
Elements that can form coordinate covalent bonds
Are there elements that are more likely to provide the two electrons for a coordinate covalent bond? If so, why?
- Thu Nov 07, 2019 1:01 pm
- Forum: Bond Lengths & Energies
- Topic: Bond lengths in resonance structures
- Replies: 2
- Views: 187
Bond lengths in resonance structures
How do we determine the bond length in resonance structures? Is it just the average of all the bond lengths?
- Thu Nov 07, 2019 1:00 pm
- Forum: Bond Lengths & Energies
- Topic: Bond Length differences
- Replies: 2
- Views: 181
Bond Length differences
Why is a double bond not half the length of a single bond?
- Thu Nov 07, 2019 12:58 pm
- Forum: Dipole Moments
- Topic: Induced Dipole
- Replies: 4
- Views: 261
Induced Dipole
How is a dipole induced?
- Thu Nov 07, 2019 12:51 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizability of Anions
- Replies: 3
- Views: 166
Polarizability of Anions
Are more negatively charged anions more polarizable or are less negatively charged anions more polarizable why?
- Sun Nov 03, 2019 10:07 am
- Forum: Bond Lengths & Energies
- Topic: Bond Strength
- Replies: 6
- Views: 399
Bond Strength
Why are shorter bond lengths stronger?
- Sun Nov 03, 2019 10:06 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge Stability
- Replies: 3
- Views: 211
Formal Charge Stability
Why are molecules with lower formal charge more stable?
- Sun Nov 03, 2019 10:02 am
- Forum: Electronegativity
- Topic: electronegativity trend
- Replies: 9
- Views: 633
electronegativity trend
Why does electronegativity decrease going down the column?
- Sun Nov 03, 2019 10:01 am
- Forum: Dipole Moments
- Topic: Significance
- Replies: 2
- Views: 97
Significance
What is the significance of dipole moments in chemistry?
- Sun Nov 03, 2019 9:59 am
- Forum: Octet Exceptions
- Topic: Octet Exceptions
- Replies: 1
- Views: 75
Octet Exceptions
How can some elements accommodate more than 8 valence electrons but others can't?
- Wed Oct 23, 2019 9:27 pm
- Forum: Ionic & Covalent Bonds
- Topic: lewis structures for diff bonds
- Replies: 5
- Views: 155
Re: lewis structures for diff bonds
Yes, we still draw lewis structures for both ionic and covalent bonds. In class potassium chloride was drawn as K+ [ Cl ]-. The Cl has 8 electrons surrounding it.
- Wed Oct 23, 2019 9:24 pm
- Forum: Resonance Structures
- Topic: defintion
- Replies: 7
- Views: 410
Re: defintion
Yes, it is when some lewis structures have multiple bonds in different equivalent locations.
- Wed Oct 23, 2019 9:22 pm
- Forum: Ionic & Covalent Bonds
- Topic: Octet Rule
- Replies: 6
- Views: 197
Octet Rule
Why are H, He, Li, and Be exceptions to the octet rule?
- Wed Oct 23, 2019 9:20 pm
- Forum: Ionic & Covalent Bonds
- Topic: Double Bond vs Single Bond Length
- Replies: 6
- Views: 525
Double Bond vs Single Bond Length
Are double bonds shorter than single bonds because they're stronger? If so, then why is the observed N-O bond length in the NO3- 1.24 A.
- Wed Oct 23, 2019 9:16 pm
- Forum: Ionic & Covalent Bonds
- Topic: Resonance
- Replies: 12
- Views: 415
Resonance
Why are compounds with resonance considered more stable?
- Sun Oct 20, 2019 3:15 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Opposite Spin
- Replies: 5
- Views: 291
Opposite Spin
Why do electrons in an orbital have opposite spins?
- Sun Oct 20, 2019 3:12 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Exceptions
- Replies: 5
- Views: 284
Electron Configuration Exceptions
What are the exceptions to electron configuration, and why do those exceptions exist?
- Sun Oct 20, 2019 3:11 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Plane
- Replies: 3
- Views: 114
Nodal Plane
What is the purpose of a nodal plane and why does s- orbitals not have it but others do?
- Sun Oct 20, 2019 3:10 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers
- Replies: 2
- Views: 108
Quantum Numbers
When does ms equal +1/2 and when does it equal -1/2
- Sun Oct 20, 2019 3:07 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect
- Replies: 7
- Views: 278
Photoelectric Effect
Can someone explain why increasing the intensity of light does not help eject an electron again?
- Sat Oct 12, 2019 12:21 am
- Forum: Properties of Electrons
- Topic: Wave properties
- Replies: 5
- Views: 240
Re: Wave properties
All matter has wavelike properties, but only moving objects with extremely small mass such as electrons can be thoroughly observed/detected.
- Sat Oct 12, 2019 12:13 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Help with 1A. 11
- Replies: 1
- Views: 82
Re: Help with 1A. 11
The quantum number for the lower energy level is the same for every absorption line in each series. For example, the Lyman series has a lower energy level of n=1 for all of the absorption lines.
- Sat Oct 12, 2019 12:04 am
- Forum: Einstein Equation
- Topic: Cancelling out units
- Replies: 2
- Views: 354
Re: Cancelling out units
The units of h, which is Planck's Constant is Js. Joules=kgm^2s^-2. Mass is in the units of kilogram, and velocity has units of m/s. Therefore you have [(kgm^2s^-2)(s)] / [(kg)(m/s)]. The kilograms cancel out: [( kg m^2s^-2)(s)] / [( kg )(m/s)]. The seconds cancel out: [( kg m^2 s^-2 )( s )] / [( kg...
- Fri Oct 11, 2019 11:51 pm
- Forum: Properties of Light
- Topic: Homework question 1E.5?
- Replies: 1
- Views: 107
Re: Homework question 1E.5?
a) False because electrons in lower energy levels/orbitals shield electrons in higher ones due to electron repulsion. Thus, electrons in higher orbital levels experience less attraction to the nucleus. b) True c) False because electrons attraction to the nucleus decrease as l increases, decreasing t...
- Fri Oct 11, 2019 11:39 pm
- Forum: Properties of Light
- Topic: Question 1B7
- Replies: 1
- Views: 65
Re: Question 1B7
a) Using the equation c=vλ, we can replace v in the equation E=hv with c/λ. E=hc/λ=(6.626x10^-34)(2.997x10^8)/(589x10^-9)=3.37X10^-19J b) For this problem I used dimensional analysis: 5.00x10^-3 g Na (1 mol Na/22.99g Na ) ( 6.022x10^23 atoms/1 mol Na)( 3.37x10^-19 J/ 1 atom)= 44.1 J c) Dimensional a...
- Fri Oct 04, 2019 8:26 pm
- Forum: SI Units, Unit Conversions
- Topic: Rounding
- Replies: 6
- Views: 379
Re: Rounding
There is no need to directly indicate it. Just write as many digits as you consider necessary. I usually do two or three digits more than the sig figs for the final answer.
- Fri Oct 04, 2019 8:23 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: G23
- Replies: 2
- Views: 179
G23
In medicine it is sometimes necessary to prepare solutions with a specific concentration of a given ion. A lab technician has made up 100.0 mL of a solution containing 0.50 g of NaCl and 0.30 g of KCl, as well as glucose and other sugars. What is the concentration of chloride ions in the solution? D...
- Fri Oct 04, 2019 8:11 pm
- Forum: Significant Figures
- Topic: Sig Figs
- Replies: 3
- Views: 108
Sig Figs
If there is both multiplication/division and addition/subtraction in a problem, how do we determine the sig figs for the final answer?
- Fri Oct 04, 2019 8:09 pm
- Forum: Balancing Chemical Reactions
- Topic: Question on H15
- Replies: 3
- Views: 264
Re: Question on H15
A molecule is aqueous if it can be dissolved in water.
- Fri Oct 04, 2019 8:03 pm
- Forum: Balancing Chemical Reactions
- Topic: M9
- Replies: 2
- Views: 119
M9
Can someone refresh me on how to write ionic equations?