## Search found 49 matches

Sun Dec 08, 2019 5:22 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: polarisability
Replies: 3
Views: 85

### Re: polarisability

We never had to use the formula to do any calculations. if anything this would be a conceptual question,
Sun Dec 08, 2019 5:14 pm
Forum: Resonance Structures
Topic: Best Resonance Structure
Replies: 5
Views: 104

### Re: Best Resonance Structure

All the resonance structures should have the same charge because the only thing that is changing is the placement of the bonds.
Sun Dec 08, 2019 5:09 pm
Forum: Polyprotic Acids & Bases
Topic: Calculating pH of polyprotic acid
Replies: 2
Views: 55

### Re: Calculating pH of polyprotic acid

We would calculate it regularly because the second dissociation does not cause a large enough change in the pH for there to be a need to consider it.
Sun Dec 08, 2019 5:05 pm
Forum: Conjugate Acids & Bases
Topic: 6A.3
Replies: 2
Views: 53

### Re: 6A.3

The acid molecule will react with water to produce H30+ and a conjugate base which can reaccept the proton.
Sun Dec 08, 2019 5:02 pm
Forum: Lewis Acids & Bases
Topic: Lewis Acids
Replies: 3
Views: 66

### Re: Lewis Acids

Lewis acids are molecules that are often positively charged that would bond to an atom with a lone pair such as H+.
Sun Dec 08, 2019 5:01 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: enthalpy?
Replies: 3
Views: 30

### Re: enthalpy?

No we will not be tested on anything related to enthalpy.
Sun Dec 08, 2019 4:58 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: pH Calculation
Replies: 3
Views: 38

### Re: pH Calculation

For strong acids like HCl you would assume full dissociation and so you would just take the negative log of the molarity given because that is how many H30+ ions will be produced as well.
Sun Dec 08, 2019 4:55 pm
Forum: Bronsted Acids & Bases
Topic: NH3
Replies: 5
Views: 80

### Re: NH3

NH3 is a molecule that is amphoteric so it can act as a base or acid. Therefore, you can not assume anything.
Sun Dec 01, 2019 11:58 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Explain VSEPR conceptually
Replies: 12
Views: 124

### Re: Explain VSEPR conceptually

VSEPR provides a 3D model for a molecule based on the regions of electron density.
Sun Dec 01, 2019 11:56 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Linear VSEPR model
Replies: 21
Views: 193

### Re: Linear VSEPR model

You determine VSEPR based on the regions of electron density, and lone pairs attached to the central atom are considered another region of electron density.
Sun Dec 01, 2019 11:53 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Test 2
Replies: 6
Views: 75

### Re: Test 2

I believe the test will be handed back in discussion this week with your grade on it.
Sun Dec 01, 2019 11:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs linear
Replies: 56
Views: 511

### Re: Bent vs linear

A molecule is bent rather than linear because when a lone pair has more repulsion than that of another atom, so even though the other two atoms in the bent shape are closer together, this is still a more optimal shape.
Sun Dec 01, 2019 11:50 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Breaking of pi and sigma bonds
Replies: 4
Views: 35

### Re: Breaking of pi and sigma bonds

Sigma bonds allow for rotation while pi bonds do not, so the pi bonds would break only.
Sun Nov 24, 2019 11:59 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pairs on Cenrtral Atom
Replies: 11
Views: 80

### Re: Lone Pairs on Cenrtral Atom

Lone pairs have the highest repulsion, so even if the attached atoms are closer together when there is a lone pair, the molecule is more stable.
Sun Nov 24, 2019 11:57 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: melting point
Replies: 8
Views: 63

### Re: melting point

If a bond broke, the melting point would decrease because that means less energy is required to break the total bonds in the molecule.
Sun Nov 24, 2019 11:55 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: energy
Replies: 1
Views: 25

### Re: energy

The lone pairs have the highest repulsion, so the molecule is more stable if the atoms are further from the lone pairs because repulsion increases potential energy rapidly after a certain point.
Sun Nov 24, 2019 11:53 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR formula
Replies: 5
Views: 31

### Re: VSEPR formula

Yes we need to know the bond angles based on the molecular shape.
Sun Nov 24, 2019 11:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: electron and molecular geometry of H20
Replies: 3
Views: 30

### Re: electron and molecular geometry of H20

The electron arrangement of H20 would be tetrahedral, but the molecular shape would be bent/angular.
Sun Nov 10, 2019 11:04 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizability for Final
Replies: 2
Views: 35

### Re: Polarizability for Final

As previously stated, I would know the general trends of polarizability and polarizing power.
Sun Nov 10, 2019 11:03 pm
Forum: Resonance Structures
Topic: octet v. expanded octet
Replies: 5
Views: 45

### Re: octet v. expanded octet

You would not draw an expanded octet for a single atom. For a molecule, you would show an expanded octet by surpassing the octet rule such as an atom having 5 covalent bonds.
Sun Nov 10, 2019 11:00 pm
Forum: Bond Lengths & Energies
Topic: London Forces
Replies: 6
Views: 56

### Re: London Forces

Yes, because all molecules have electrons and these electrons can congregate by chance.
Sun Nov 10, 2019 10:58 pm
Forum: Electronegativity
Topic: Electron affinity
Replies: 6
Views: 45

### Re: Electron affinity

Electronegativity and electron affinity increase towards the upper right.
Sun Nov 10, 2019 10:56 pm
Forum: Electronegativity
Topic: Atom size
Replies: 16
Views: 262

### Re: Atom size

Atomic radius increases in the opposite direction from electronegativity.
Sun Nov 03, 2019 11:36 pm
Forum: Quantum Numbers and The H-Atom
Topic: Magnetic Quantum Number
Replies: 3
Views: 27

### Re: Magnetic Quantum Number

it is always plus or minus 1/2 and you cannot find the spin orientation, rather you essentially assign it yourself.
Sun Nov 03, 2019 11:35 pm
Forum: Quantum Numbers and The H-Atom
Topic: 4th Quantum Number
Replies: 3
Views: 31

### Re: 4th Quantum Number

There is no way to calculate or find the fourth quantum number. As long as two electrons in the same orbital do not have the same spin you are good.
Sun Nov 03, 2019 11:34 pm
Forum: DeBroglie Equation
Topic: 1B. 21
Replies: 5
Views: 109

### Re: 1B. 21

That information has nothing to do with the calculations because they give you the actual mass of the baseball.
Sun Nov 03, 2019 11:32 pm
Forum: DeBroglie Equation
Topic: unit of wavelength
Replies: 5
Views: 116

### Re: unit of wavelength

when you work with the equation, you use meters, but often you convert the final answer into nanometers because it is more visually appealing this way.
Sun Nov 03, 2019 11:28 pm
Forum: DeBroglie Equation
Topic: 1B.15 c)
Replies: 1
Views: 41

### Re: 1B.15 c)

basically you use the equation Ek = work + 1/2xmassxvelocity^2 and plug in the answer from part b as the value for the work function. Then you should get around 8.8x10^-9 m which you convert to nm.
Sun Oct 27, 2019 5:39 pm
Forum: Lewis Structures
Topic: Lone pair
Replies: 8
Views: 51

### Re: Lone pair

A lone pair is just the pair of electrons not used in the chemical bond, which is why they are lonely.
Sun Oct 27, 2019 5:34 pm
Forum: Ionic & Covalent Bonds
Topic: Double bond placement
Replies: 15
Views: 111

### Re: Double bond placement

Double bond placement does not need to be in a specific spot as long as the octet rule is fulfilled for all the atoms.
Sun Oct 27, 2019 5:27 pm
Forum: Ionic & Covalent Bonds
Topic: Resonance
Replies: 10
Views: 84

### Re: Resonance

Resonance means that a molecule can have a certain bond in multiple different areas while still being the same molecule. Lewis structures can only show one of these formations at a time.
Sun Oct 27, 2019 5:24 pm
Forum: Lewis Structures
Topic: Reasoning for the octet
Replies: 3
Views: 42

### Re: Reasoning for the octet

Atoms are the most stable with a full valence shell, and as you stated, the s and p orbitals can hold a total of 8 electrons, so the octet being filled is the goal.
Sun Oct 27, 2019 5:20 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Water molecules
Replies: 9
Views: 341

### Re: Water molecules

Water molecules use both Hydrogen atoms to form a hydrogen bond and not both to form one bond.
Mon Oct 21, 2019 12:00 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Best Way To Study?
Replies: 56
Views: 704

### Re: Best Way To Study?

i think attending lecture and taking good notes is a good way to study. After, review the textbook and consolidate the information into a more cohesive "cheat sheet" in order to highlight the specific topics.
Sun Oct 20, 2019 11:59 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Formulas or Experiments
Replies: 2
Views: 29

### Re: Formulas or Experiments

I think we should know the experiments in order to be able to understand the concepts behind the formulas.
Sun Oct 20, 2019 11:58 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Homework Problem 1A #3
Replies: 3
Views: 54

### Re: Homework Problem 1A #3

the extent of change refers to the wave's slope, which correlates directly with frequency.
Sun Oct 20, 2019 11:55 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Memorizing Wavelengths and Frequencies?
Replies: 2
Views: 28

### Re: Memorizing Wavelengths and Frequencies?

I agree I would just memorize which series goes with which level and the types of wavelengths that are associated with them. I would also know the range of each wave type.
Sun Oct 20, 2019 11:50 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Homework 1A.9
Replies: 1
Views: 31

### Re: Homework 1A.9

You basically use the formula wavelength=speed of light x frequency in order to find the frequency and wavelength as needed. To find the energy of the photon use the formula E=Planck's constant x frequency. Based on the wavelength, you can determine what the activity is.
Sun Oct 13, 2019 9:37 pm
Forum: Properties of Electrons
Topic: wave-like vs particle-like
Replies: 2
Views: 24

### Re: wave-like vs particle-like

Photons act as a wave but on a much smaller scale act as individual entities.
Sun Oct 13, 2019 9:27 pm
Forum: Photoelectric Effect
Topic: Wavelength, Frequency, and Intensity
Replies: 7
Views: 52

### Re: Wavelength, Frequency, and Intensity

intensity is the number of photons emitted and frequency is the number of waves during a certain period
Sun Oct 13, 2019 9:25 pm
Forum: Photoelectric Effect
Topic: Wavelength, Frequency, and Intensity
Replies: 7
Views: 52

### Re: Wavelength, Frequency, and Intensity

wavelength and frequency are inversely related so when wavelength increases, frequency decreases, which means there is less intensity coming from the wave, so less energy.
Sun Oct 13, 2019 9:21 pm
Forum: Photoelectric Effect
Topic: Waves
Replies: 4
Views: 47

### Waves

What is the relationship between wavelength, frequency and amplitude?
Sun Oct 13, 2019 9:12 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Atom Spectroscopy
Replies: 2
Views: 63

### Re: Atom Spectroscopy

I am not sure but so far we have only learned how to complete these problems using the equation derived from the experiment that used hydrogen atoms.
Sun Oct 06, 2019 11:55 pm
Forum: Balancing Chemical Reactions
Topic: H 1
Replies: 6
Views: 177

### H 1

It appears that balancing the chemical equation Cu 1 SO 2 S
CuO 1 S would be simple if we could just add another O atom to the
product side: Cu 1 SO 2 S CuO 1 S 1 O. (a) Why is that balancing
procedure not allowed? (b) Balance the equation correctly.

I am confused about part a.
Sun Oct 06, 2019 11:54 pm
Forum: Molarity, Solutions, Dilutions
Topic: G 25
Replies: 7
Views: 165

### G 25

Practitioners of the branch of alternative medicine known as homeopathy claim that very dilute solutions of substances can have an effect. Is the claim plausible? To explore this question, suppose that you prepare a solution of a supposedly active substance, X, with a molar concentration of 0.10 mol...
Sun Oct 06, 2019 11:52 pm
Forum: SI Units, Unit Conversions
Topic: Unit Conversions
Replies: 6
Views: 110

### Re: Unit Conversions

I believe that we should know the conversions as it will help with the efficiency of our test taking.
Sun Oct 06, 2019 11:50 pm
Forum: Molarity, Solutions, Dilutions
Topic: G 11
Replies: 2
Views: 56

### G 11

A medical researcher investigating the properties of intravenous solutions prepared a solution containing 0.278 m C6H12O6 (glucose). What volume of solution should the researcher use to provide 4.50 mmol C6H12O6? I'm not sure whether the answer is 0.016 or 0.02. How do we know how many sig figs to r...
Sun Oct 06, 2019 11:47 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: E 17
Replies: 4
Views: 126

### Re: E 17

Thank you for answering my question
Sun Oct 06, 2019 11:44 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: E 17
Replies: 4
Views: 126

### E 17

Which sample in each of the following pairs contains the
greater number of moles of atoms? (a) 75 g of indium or 80 g of
tellurium; (b) 15.0 g of P or 15.0 g of S; (c) 7.36 3 10 27 atoms of
Ru or 7.36 3 10 27 atoms of Fe.