Search found 60 matches

by AniP_2D
Wed Jan 22, 2020 5:17 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Conjugate Seesaw
Replies: 3
Views: 15

Re: Conjugate Seesaw

The conjugate seesaw simply states that the stronger the acid, the weaker its conjugate base and the stronger a base, the weaker its conjugate acid.
by AniP_2D
Wed Jan 22, 2020 5:15 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Solids and Liquids
Replies: 6
Views: 19

Re: Solids and Liquids

Solids and liquids are not included in the equation for the K constant, only gases and aqueous solutions.
by AniP_2D
Wed Jan 22, 2020 4:16 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Pressure changes
Replies: 7
Views: 21

Re: Pressure changes

If the pressure is increased, the system shifts to the side with less moles, and if the pressure is decreased, the system shifts to the side with more moles.
by AniP_2D
Wed Jan 22, 2020 4:11 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Prep for Test 1
Replies: 13
Views: 78

Re: Prep for Test 1

No there are no specific values that you need to memorize. A helpful thing to know however, for the test is how to go from Ka to Kb and how to find the pH and pOH given the values of Ka or Kb.
by AniP_2D
Wed Jan 22, 2020 4:08 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J 5: increase in pressure
Replies: 4
Views: 39

Re: 5J 5: increase in pressure

For part B, you do not take C into account since it is a solid so technically the left side would have 1 mol and the right side would have 2 mols, hence the reason why the system would shift to the left. For D, the amount of moles on both sides equals 2, so since the amount of moles are equal, there...
by AniP_2D
Sun Jan 19, 2020 9:17 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5% vs. K < 10^-3
Replies: 3
Views: 17

Re: 5% vs. K < 10^-3

When K<10^-3, you are allowed to approximate and the 5% rule is just a means of confirming that your approximation is valid.
by AniP_2D
Sun Jan 19, 2020 9:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Le Chatelier's Principle
Replies: 4
Views: 16

Re: Le Chatelier's Principle

Adding on to this, does the Le Chatelier's Principle only apply for the partial pressures or do I need to know how to apply it for concentrations? Le Chatelier's Principle is applied to both concentrations and partial pressures, however I believe that you would apply the principle to concentrations...
by AniP_2D
Sun Jan 19, 2020 8:59 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Relationship between pressure and volume
Replies: 10
Views: 19

Re: Relationship between pressure and volume

According to the ideal gas law, PV=nRT, pressure and volume are inversely proportional.
by AniP_2D
Sun Jan 19, 2020 8:56 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J.1
Replies: 4
Views: 15

Re: 5J.1

The reason why CO2 would decrease when CO decreases is because, according to Le Chatelier's principle, the system will shift to the left of the reaction in order to provide a balance, meaning that CO2 will decrease in order to contribute to this balance.
by AniP_2D
Sun Jan 19, 2020 8:52 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Le Chatelier's Principle
Replies: 7
Views: 20

Re: Le Chatelier's Principle

Le Chatelier's principle is significant because we can use it to predict what may happen to a substance when changes in things like temperature and concentration are inflicted. I think it applies to all reversible reaction.
by AniP_2D
Mon Jan 13, 2020 3:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kw calcuation
Replies: 5
Views: 22

Re: Kw calcuation

Since water is a liquid, it is omitted from the equilibrium constant, giving the denominator in this specific equilibrium constant a value of 1.
by AniP_2D
Mon Jan 13, 2020 3:24 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5I.27
Replies: 8
Views: 33

Re: 5I.27

Equilibrium composition means the stating the concentration for each products and reactant in the chemical equation.
by AniP_2D
Mon Jan 13, 2020 3:22 pm
Forum: Ideal Gases
Topic: Molar Concentration
Replies: 4
Views: 24

Re: Molar Concentration

Depending if there is an initial amount of products or reactants, the one with no amount will increase and the other will decrease. To determine how many values of X increase or decrease, you must see if the reactant and products have a coefficient in the balanced equation.
by AniP_2D
Mon Jan 13, 2020 3:19 pm
Forum: Ideal Gases
Topic: converting Kc to Kp
Replies: 13
Views: 72

Re: converting Kc to Kp

If you know the molar concentration, then you should technically be able to figure out the volume.
by AniP_2D
Mon Jan 13, 2020 3:16 pm
Forum: Ideal Gases
Topic: When to use this equation
Replies: 14
Views: 66

Re: When to use this equation

An example of when to use this function is if you are given pressure and need to find concentration. You can also use it to find the pressure if you are given concentration.
by AniP_2D
Sun Dec 01, 2019 8:54 pm
Forum: Hybridization
Topic: 2F.3
Replies: 3
Views: 20

Re: 2F.3

They used this version of the Lewis structure due to formal charge.
by AniP_2D
Sun Dec 01, 2019 8:52 pm
Forum: Hybridization
Topic: Hybridization
Replies: 7
Views: 59

Re: Hybridization

Yes I think that should be it. An easy way to check if your hybridization is correct is that the exponents of the s, p, and d orbitals should add up to the amount of electron clouds. So sp^2 has an electron density of 3 since 2+1=3.
by AniP_2D
Sun Dec 01, 2019 8:50 pm
Forum: Hybridization
Topic: Hybridization (Lone Pairs)
Replies: 4
Views: 33

Re: Hybridization (Lone Pairs)

Yes they do. You would count the lone pairs as an additional bonding site. So for example, a molecule with 2 shared pairs (2 sigma bonds) and one lone pair would have an electron density equal to 3. This would lead the molecule to have a hybridization of sp^2.
by AniP_2D
Sun Dec 01, 2019 8:45 pm
Forum: Hybridization
Topic: Order When Writing
Replies: 5
Views: 27

Re: Order When Writing

Both are correct but I think the preferred way is to right it beginning with d.
by AniP_2D
Sun Dec 01, 2019 8:43 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number
Replies: 9
Views: 51

Re: Oxidation Number

I think the oxidation number should always be included in Roman numerals after the transition metal because since the metal can have different oxidation numbers, it is important to specify the oxidation number.
by AniP_2D
Sun Nov 24, 2019 8:02 pm
Forum: Hybridization
Topic: Sigma and Pi bonds
Replies: 13
Views: 57

Re: Sigma and Pi bonds

When drawing a molecule, you would go about drawing the bonds as you normally would and just label the sigma bonds and pi bonds.
1 bond= 1 sigma, 0 pi
2 bonds=1 sigma, 1 pi
3 bonds= 1 sigma, 2 pi
by AniP_2D
Sun Nov 24, 2019 7:59 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity
Replies: 5
Views: 28

Re: Polarity

If a molecule has dipole moments that do not cancel, then it is polar. If the dipole moments do cancel, then it is non-polar. One general rule to know is that molecules with a tetrahedral shape generally are non-polar unless the the outer atoms are not identical. Also while linear shaped molecules a...
by AniP_2D
Sun Nov 24, 2019 7:55 pm
Forum: Hybridization
Topic: Hybridization
Replies: 3
Views: 27

Re: Hybridization

To determine the hybridization you would look at the electron density of a molecule.
by AniP_2D
Sun Nov 24, 2019 7:50 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs linear
Replies: 56
Views: 287

Re: Bent vs linear

A linear shaped molecule has no lone pairs at the central atom, while a bent shaped molecule does have one or two lone pairs at the central atom.
by AniP_2D
Sat Nov 16, 2019 12:47 pm
Forum: Dipole Moments
Topic: London forces
Replies: 9
Views: 53

Re: London forces

They are considered universal because every molecule, polar or non-polar, has London Dispersion Forces. However, it is important to know that London Dispersion Forces are the most prominent intermolecular force in non-polar molecules.
by AniP_2D
Sat Nov 16, 2019 12:42 pm
Forum: Dipole Moments
Topic: CH
Replies: 3
Views: 32

Re: CH

Anytime a C atom bonds with an H atom (C2H2, CH6, C10H5, etc.), know that it is always non-polar and that there are no dipole moments.
by AniP_2D
Sat Nov 16, 2019 12:38 pm
Forum: Dipole Moments
Topic: Hydrogen bonds
Replies: 17
Views: 87

Re: Hydrogen bonds

Hydrogen bonds can only be formed when H bonds with F, O, or N.
by AniP_2D
Sat Nov 16, 2019 12:37 pm
Forum: Dipole Moments
Topic: Polarity
Replies: 12
Views: 75

Re: Polarity

Another tip is that if the atoms around the central atom are not the same (ex. CH3F), then the molecule is very likely to be polar.
by AniP_2D
Sat Nov 16, 2019 12:31 pm
Forum: Dipole Moments
Topic: Hydrogen Bond
Replies: 7
Views: 46

Re: Hydrogen Bond

A hydrogen bond is a type of dipole-dipole interaction found amongst polar molecules. It is very strong, meaning that molecules that have hydrogen bonds have a high boiling point. Hydrogen bonds can only occur when an H atom bonds with either a F, O, or N atom.
by AniP_2D
Sat Nov 16, 2019 12:29 pm
Forum: Dipole Moments
Topic: Dipole-Dipole vs. Dipole-Induced Dipole
Replies: 3
Views: 20

Dipole-Dipole vs. Dipole-Induced Dipole

What is the difference between a dipole-dipole force versus a dipole-induced dipole force?
by AniP_2D
Sun Nov 10, 2019 12:47 pm
Forum: Octet Exceptions
Topic: octet exceptions
Replies: 11
Views: 104

Re: octet exceptions

C, N, O, F, and Ne are the main elements that must follow the octet rule. There are elements like hydrogen that only need two and those like boron that need 6. Also any element past phosphorus can hold more than 8 electrons.
by AniP_2D
Fri Nov 08, 2019 11:26 am
Forum: Lewis Structures
Topic: Exceptions to Octet Rule
Replies: 7
Views: 33

Re: Exceptions to Octet Rule

Yes, elements Phosphorus and onward can hold more than 8 electrons in their shell and thus can exceed the octet rule.
by AniP_2D
Fri Nov 08, 2019 11:24 am
Forum: Formal Charge and Oxidation Numbers
Topic: central atom
Replies: 21
Views: 103

Re: central atom

Yes, when drawing a lewis structure, the optimal structure will have a central atom with formal charge 0. It would be ideal for all of the atoms to have a formal charge of 0, but since this is not always possible your main concern should be to make the central atom have a formal charge of 0.
by AniP_2D
Fri Nov 08, 2019 11:21 am
Forum: Octet Exceptions
Topic: Why can't Aluminum have an expanded octet?
Replies: 5
Views: 63

Re: Why can't Aluminum have an expanded octet?

Al can not have an expanded octet because only elements Phosphorus and onward can have more than 8 electrons. However, Al is one the exceptions to the octet rule in the case that it can have less than 8 electrons.
by AniP_2D
Fri Nov 08, 2019 11:18 am
Forum: Electronegativity
Topic: Determining Electronegativity
Replies: 4
Views: 45

Re: Determining Electronegativity

The less electronegative a compound is, the more ionic it will be. When looking at the periodic table, you can confirm that Cl is more electronegative than Br, meaning that SiCl is more electronegative. With this information, you can determine that SiBr is more ionic than SiCl.
by AniP_2D
Sat Nov 02, 2019 10:25 am
Forum: Quantum Numbers and The H-Atom
Topic: determining the number of orbitals
Replies: 7
Views: 58

Re: determining the number of orbitals

You would use m(l) to determine the number of orbitals. For example, if you were given n=2 and l=1, the m(l) would be -1,0,1 which tells you that there are 3 orbitals.
by AniP_2D
Sat Nov 02, 2019 10:15 am
Forum: Octet Exceptions
Topic: Octet Exception
Replies: 5
Views: 42

Re: Octet Exception

Any element past Phosphorus (including P) are an exception to the octet rule and can hold more than 8 electrons.
by AniP_2D
Sat Nov 02, 2019 10:11 am
Forum: Lewis Structures
Topic: central atom
Replies: 16
Views: 126

Re: central atom

The least electronegative atom is the central atom when drawing Lewis structures.
by AniP_2D
Sat Nov 02, 2019 10:08 am
Forum: Formal Charge and Oxidation Numbers
Topic: Minimizing Formal Charges
Replies: 5
Views: 43

Re: Minimizing Formal Charges

In the scenario you just described, it would be best to have 3 formal charges of 0 and one +1. When trying to draw the most stable lewis structure, you want the formal charge of the atoms to be as close to 0 as possible.
by AniP_2D
Tue Oct 29, 2019 12:30 pm
Forum: Lewis Structures
Topic: Homework problem 2C.3
Replies: 5
Views: 44

Re: Homework problem 2C.3

For now, I don't think we're expected to know the formulas.
by AniP_2D
Tue Oct 29, 2019 12:19 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: HW Question 2A5
Replies: 3
Views: 34

Re: HW Question 2A5

Cu is one of two exceptions when it comes to electron configurations (the other is Cr), so its electron configuration is [Ar]3d^10 4s^1. So when you subtract an electron due to the positive charge in part a, you would end up with the electron configuration [Ar]3d^10 since you subtracted the electron...
by AniP_2D
Tue Oct 29, 2019 12:04 pm
Forum: Resonance Structures
Topic: stability
Replies: 2
Views: 30

Re: stability

Usually with different resonance structures, there are different formal charges. A formal charge of 0 means that the molecule is most stable so you want to draw the resonance structure that will give you a formal charge of 0, making it the most stable.
by AniP_2D
Sat Oct 26, 2019 11:49 am
Forum: Quantum Numbers and The H-Atom
Topic: Magnetic Quantum Number
Replies: 5
Views: 36

Re: Magnetic Quantum Number

You would have to write out all 5 values instead of just saying 5.
by AniP_2D
Sat Oct 26, 2019 11:47 am
Forum: Quantum Numbers and The H-Atom
Topic: 1D.19
Replies: 3
Views: 32

Re: 1D.19

To determine the number of orbitals you would look at ml from l.
by AniP_2D
Sat Oct 26, 2019 11:11 am
Forum: Lewis Structures
Topic: HW question 2B.3
Replies: 2
Views: 33

Re: HW question 2B.3

There needs to be a double bond between Si and the two oxygens because the double bonds allow for the octet rule to be satisfied for Si. If you were to use single bonds, Si would only have 4 electrons when 8 are needed.
by AniP_2D
Fri Oct 18, 2019 11:26 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: hw problem 1D.21
Replies: 2
Views: 28

Re: hw problem 1D.21

The subshell notation is basically the n-value and and the subshell that corresponds to l. If l=0, s is the subshell, l=1 then p, l=2 then d, and l=3 f So for (a) the subshell notation would be 5d and for (b) it would be 1s For orbitals you would just look and see how many possible ml values the cer...
by AniP_2D
Fri Oct 18, 2019 11:13 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Homework 1D. 23
Replies: 2
Views: 27

Re: Homework 1D. 23

(a) a is 3 orbitals because the possible outcomes for ml are -1, 0, 1 (b) b is only 1 orbital because the value of ml is already given to you. Since only 1 value of ml is given (ml=-2), there is only 1 orbital (c) for n=2, the possible l values are 0 and 1. The possible ml values for l=0 are ml=0 an...
by AniP_2D
Fri Oct 18, 2019 11:05 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Spin State
Replies: 6
Views: 51

Spin State

Can someone please explain the concept of a spin state? I am having trouble understanding what a spin state is and what it means in regards to the orbital. Thank you.
by AniP_2D
Fri Oct 18, 2019 11:02 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: quantum number n, l, m
Replies: 13
Views: 87

Re: quantum number n, l, m

n is the principal quantum number and it tells you what shell the electron is in l is the angular momentum quantum number and it describes shape. l=0,1,2,...n-1 Depending on what your l is you can determine whether your electron is in the s, p, d, or f orbital ml is the magnetic quantum number and i...
by AniP_2D
Fri Oct 18, 2019 10:29 am
Forum: Properties of Light
Topic: 1A.9 Energy of Photon
Replies: 12
Views: 79

Re: 1A.9 Energy of Photon

You would use Energy=(Planck's constant)*(frequency) to find the energy of the photon. If you do not have the value of frequency, you would use speed of light=(wavelength)*(frequency) to find frequency and then plug it into the equation for energy.
by AniP_2D
Fri Oct 11, 2019 7:03 pm
Forum: Einstein Equation
Topic: Units
Replies: 17
Views: 632

Re: Units

Kelvin Chung 1C wrote:Do we need to know the SI unit equivalents for each term, like the joule?


I am not sure if you need to know them, but for the quantum section it would extremely helpful to know that a J is equal to kg*m^2*s^-2
by AniP_2D
Fri Oct 11, 2019 6:45 pm
Forum: Empirical & Molecular Formulas
Topic: empirical = molecular?
Replies: 15
Views: 167

Re: empirical = molecular?

If the molecular formula can no longer be simplified, then it is viewed as both the molecular and empirical formula.
by AniP_2D
Fri Oct 11, 2019 6:42 pm
Forum: Limiting Reactant Calculations
Topic: Fundamentals M.5
Replies: 3
Views: 71

Re: Fundamentals M.5

You would use the amount of moles of the limiting reactant to find the amount of moles used of the excess reactant using the stoichiometric coefficients of the balanced chemical equation. Once you find out how many moles of the excess have been used, you can then subtract that amount from the amount...
by AniP_2D
Fri Oct 11, 2019 6:34 pm
Forum: Properties of Light
Topic: Homework Question 1A.7
Replies: 2
Views: 20

Re: Homework Question 1A.7

It is a typo as the correct answer is 150 pm.
by AniP_2D
Fri Oct 11, 2019 6:23 pm
Forum: Einstein Equation
Topic: E=hv
Replies: 8
Views: 68

Re: E=hv

h represents Planck's constant, which is 6.626*10^-34 J*s
by AniP_2D
Sat Oct 05, 2019 12:47 pm
Forum: Significant Figures
Topic: Sig Fig Addition and Subtraction
Replies: 5
Views: 74

Re: Sig Fig Addition and Subtraction

Usually what I do when I'm adding/subtracting or multiplying/dividing, and the result is too long of a number to write down fully, is to just round the answer to 2 digits more than the amount of sig figs needed and then when I reach the final answer I will then round to the amount of sig figs needed.
by AniP_2D
Sat Oct 05, 2019 12:32 pm
Forum: Significant Figures
Topic: Sig Figs given in problem vs solution
Replies: 3
Views: 32

Re: Sig Figs given in problem vs solution

Yes, you should and if you are presented with values that have a different amount of sig figs, remember to use the same amount of sig figs as the value that has the least amount of sig figs for your final answer.
by AniP_2D
Sat Oct 05, 2019 11:35 am
Forum: Significant Figures
Topic: Sig Figs
Replies: 3
Views: 25

Re: Sig Figs

When you are trying to determine the amount of sig figs to use when carrying out tasks such as addition/subtraction or multiplication/division, the rule is to use the same amount of sig figs as the number with the least amount of sig figs presented in the problem.
by AniP_2D
Sat Oct 05, 2019 11:31 am
Forum: Significant Figures
Topic: Sig Figs in % Yield
Replies: 10
Views: 141

Re: Sig Figs in % Yield

Usually when you are given a decimal that is .5 or higher, you would round up to the next whole number.
by AniP_2D
Sat Oct 05, 2019 11:20 am
Forum: Significant Figures
Topic: Rules for Significant Figures
Replies: 4
Views: 72

Re: Rules for Significant Figures

There are a few rules that one must take into consideration when dealing with significant figures. 1. Any number that is not zero is considered significant. 2. Zeros are only considered significant if they are between two significant figures (any non-zero number). 3. Also, zeros that are placed afte...

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