CHEMISTRY COMMUNITY

Madeera_Mian_3B

A formula used in the textbook is (# metal atoms)(oxidation number of the metal)+(# of each ligand)(charge of each ligand)=charge of the ion, let x be the oxidation number to be determined.

Madeera_Mian_3B

The 7th edition textbook problem Fundamental J 1, identify which is a Bronsted Acid or Base: NH3, HBR, KOH, H2SO3, Ca(OH)2. How do we know which one is a Bronsted acid or base?

Madeera_Mian_3B

Bronsted Acids is a proton donor, while Bronsted Bases is a proton acceptor. On the other hand, Lewis bases is a electron donor while Lewis acids accept electrons.

Madeera_Mian_3B

When given an example we would probably need to identify if it is an acid or base like in lecture he told us BF3 and H+ are lewis acids. But that can be found with basic information about acid and bases.

Madeera_Mian_3B

I agree, to summarize the bronsted acid/base are used for protons as either a donor or acceptor. Lewis acid/bases are used for electrons as either a donor or acceptor.

Madeera_Mian_3B

When naming a coordination compound, how do we find the roman numeral used? Like in the example in class: Cobalt (II)

Madeera_Mian_3B

I agree with the comments, drawing the the molecular shape is the best way of figuring out the bond angle. It is also a good idea to think of the model in 3D so that the bond angles are easy to figure out.

Madeera_Mian_3B

I agree, whenever there is electron density there should be Hybridization. Making each molecular geometry having electron density.

Madeera_Mian_3B

Also, Pi bonds are present with bonds greater than single bonds. Sigma bonds are present in single bonds and also double and triple bonds.

Madeera_Mian_3B

Like the previous comments said it is due to the angles formed by the structure. It is sometimes easier to think of the structure in 3D, the octahedral structure becomes more apparent.

Madeera_Mian_3B

I agree with the other replies, just to add the lone pair would cause the structure to be Trigonal Pyramidal. When looking at the structure in 3D we can see that the structure looks different than the Tetrahedral structure due to the lone pair.

Madeera_Mian_3B

In Lecture sometimes we would divide the number of bonds by 360, but sometimes that does not work. I was wondering if we have to memorize the association between bond angles and their geometry or is there some other way to determine bond angles?

Madeera_Mian_3B

I agree, and to add triple bonds are shorter than double bonds due to the pull from the nucleus. Double bonds have a longer bond length due to the large distance and have a weaker pull.

Madeera_Mian_3B

Just reading over the notes and wondering how to use the Interaction potential energy equation, how do you find the polarizability and distance.

Madeera_Mian_3B

To expand on what others have said, another way to determine bond lengths is if it is a larger atom there is a larger distance causing it to have a weak bond but longer bond length.

Madeera_Mian_3B

I agree with the responses, the goal is to get the formal charge to a minimum amount or 0. This is when the structure is most stable.

Madeera_Mian_3B

As most people said, to find the central atom is the lowest ionization energy. Carbon would be the central atom since Hydrogen is never the central atom.

Madeera_Mian_3B

For Lewis Structures it is important to know the ionization energies on the periodic table. I was wondering if someone could explain the important periodic table trends (like ionization energy) needed to create a Lewis structure.

Madeera_Mian_3B

As the previous replies said, λ=h/p debroglie wave equation when the momentum or (m*v) is given. λ=hc/E is used when Energy (J) is given.

Madeera_Mian_3B

I agree with the previous replies, delta x is usually in meters (m). Delta x describes the position, sometimes the problem gives it as a radius which is the same thing as the position.

Madeera_Mian_3B

I agree with the previous comment, do not forget that it starts with 0. So the S-orbital would be 0, P-orbital would be 1, D-orbital would be 2, and the F-orbital would be 3.

Madeera_Mian_3B

I agree with the replies most of the equations and constants are given on the sheet. It was recommended that we memorize the constants and the basic equations to go through the test faster.

Madeera_Mian_3B

I agree with the previous replies, just plug in n=4 and n=2 to find the energy at each level. subtract the final and initial energy and plug in to find wavelength.

Madeera_Mian_3B

I agree with the other replies, don't worry too much on the significant figures on that problem. In most cases you should go to the lowest significant figure, but in that problem I would just go with three significant figures.

Madeera_Mian_3B

Frequency is represented by Hz (or 1/s) when doing the calculations the h units cancel with the seconds and J is left. Which shows the units for energy is J, as said before in the other replies.

Madeera_Mian_3B

Was doing the homework and noticed that for some of the problems they would use s^-1, while in others they would use Hz. Does it matter what units we use for frequency? or should they match with the rest of the calculations by using s^-1.

Madeera_Mian_3B

As everyone has said it is important to keep units in the calculation. It is important for the answer, but also for me personally it is easier to understand the equations used by seeing the units in the problem. SI units should be used during the calculations and then convert at the very end (if spe...

Madeera_Mian_3B

It is true that the moles coefficients are not "equal" on both sides. But, the process of balancing the equation is trying to make sure the atoms/elements are the same.

Madeera_Mian_3B

I agree with Ethan, making the decimal points easy to work with can make the multiplication easier. I usually find a number that satisfies most of the ratios and try to round off near the end.

Madeera_Mian_3B

I agree with Krisdylle, it would be most helpful to use significant figures in calculations. Applying significant figures to the ratios will probably not change the answer significantly. The ratios in the problem should eventually be in whole numbers so using significant figures would probably help ...

CHEMISTRY COMMUNITY

Search found 30 matches

Re: oxidation number

How to tell if it is an acid or base?

Re: Identifying the difference

Re: Lewis acid and base

Re: bronstead vs lewis

Naming

Re: Bond Angles

Re: Molecular Shape & Hybridization

Re: Pi and Sigma Bonds

Re: Molecular Shape

Re: Drawing structures

Determining Bond Angles

Re: Triple Bonds Shorter than Double Bonds

Interaction Potential Energy equation

Re: Bond Lengths

Re: Formal charge purpose

Re: Central Atom

Periodic Table Trends

Re: λ=h/p vs λ=hc/E

Re: Value of Delta X

Re: Calculate orbitals and subshells

Re: Numbers to memorize [ENDORSED]

Re: Rydberg formula

Re: Sig Figs in Problem 1.13 (6th Edition)

Re: Units

Units for v(frequency)

Re: Wavelength

Re: Mole Coefficients in Chemical Equations

Re: Rounding in Mole Ratios for Empirical Formulas

Re: SIG FIGS in ratios