CHEMISTRY COMMUNITY

ramayyala1G

I would generally just refer to pH when it talks about being less acidic unless they specifically mention pKa's. Just easier to understand.

ramayyala1G

I was just wondering if we had to memorize the amphoteric oxides, or if there's a method of determining them using the periodic table? There is the diagonal trend that Lavelle showed us in class on the periodic table. I would just use that. Just google, amphoteric compounds periodic table. It will ...

ramayyala1G

The easiest way to do this is just memorize the 7 strong acids and 8 strong bases. Anything else is weak pretty much. The strong acids are HCl, HBr, HI, HNO3, HClO4, HClO3, H2SO4, H2SeO4. The strong bases are NaOH, KaOH, CsOH, Can(OH)2, Sr(OH)2, RbOH, Ba(OH)2

ramayyala1G

I'm pretty sure a proton was transferred around since the hydrogen's are being moved around. What problem is this?

ramayyala1G

Can someone explain why BaO is basic and As2O3 and Bi2O3 amphoteric? As and Bi are metalloids and can act as either acids or bases. And BaO is basic because if you look at the reaction of BaO + H2O = Ba(OH)2, it forms hydroxide compounds meaning it s gonna be a basic compound. The general rule of t...

ramayyala1G

I'm pretty sure Ka and Kb values will be given. Or at least a table will be given. He has not said anything about having to memorize these values. Generally for these types of problems, they are usually given.

ramayyala1G

What does it mean to write the proton transfer equilibria? It basically means write the equilibrium equation. So for example, 3a, the proton transfer equilibria is H2SO4(aq) + H2O(l) (equilibrium sign) H3O+ (aq) + HSO4-(aq). By writing this equation, you are showing how the proton or the hydrogen f...

ramayyala1G

A polar covalent bond means there is unequal sharing. A regular covalent bond means that there is equal sharing of electrons. So a covalent bond with unequal sharing is a polar covalent bond.

ramayyala1G

Do they provide us with electronegative values to figure out whether it is polar covalent, non-polar covalent, or ionic? They generally won't. You usually just use the electronegativity trends of the periodic table to determine the type of bonds. At least that's what most practice problems I've don...

ramayyala1G

I mean by the logic of determining whether a bond is ionic, it's the difference between the electronegativities. If the difference is greater than 2.0 it should be more ionic. At least that was my understanding. so CsF should be more ionic.

ramayyala1G

Also keep in mind that sigma bonds allow rotation in a molecule while pi bonds do not. It may help to draw examples of this in order to visualize it.

ramayyala1G

Keep in mind you do not need to know the bond angle for this shape because it varies from molecule to molecule. 106 degrees is not the standard bent shape angle.

ramayyala1G

Generally lone pairs on the central atom will cause a decrease in bond angle due to the lone pair trying to repel the bonded pair of electrons.

ramayyala1G

It may be easier for you to just count across the periodic table. That way you won't forget to put the the configuration in increasing order. Just out of curiosity, how are you solving it because it is kinda odd to get it all out of order and then put it in order.

ramayyala1G

the easiest way to do this problem was to either know how many orbitals each subshell has or to apply the formula 2(l)+1 where if l=0 or the s subshell then, there are 2(0)+1 orbitals or 3 orbitals. This formula makes is very easy to find the orbitals. Or just count the ml numbers or count on the pe...

ramayyala1G

Cations in the d-block lose their electrons in the s-orbital because generally transition metals in the d block will try to either maintain a half or full state as it is more stable. As a result, it is easier to lose the electrons in the 4s orbital first than the d-block because it allows the elemen...

ramayyala1G

Remember Lavelle told us in class that the d-orbital is filling before the s orbital of its row meaning that it is technically of lower energy. Meaning, that electrons will be taken away from the s orbital before the d orbital.

ramayyala1G

Just remember that alot of the elements in the d-block will take an electron from their s orbital to fill the d orbital to make it half way full or all the way full in order to reach a more stable state. That is why Silver has 1 valence electron as it takes an electron from is s orbital to fill its ...

ramayyala1G

Its the same idea that we use when the d orbital comes into play in the 4s orbital. So yes, the f orbital will fill before the d orbital generally.

ramayyala1G

you should also know that dz^2 and dx^2y^2 are lobes along the plane while dzx, dyz,and dxy are lobes in-between planes to make it easier to remember how they look in the 3d planes.

ramayyala1G

I think the question is referring to the actual group 5 with transition elements such as V, Nb, Ta, and Db. In that case, the answer should be ns^2 (n-1)d^3. But the answer key says that ns^2 (n-1)d^5. Either the answer key is incorrect, or the question is actually referring to group 5 starting fro...

ramayyala1G

They are also related because each quantum number is related to each other through the equation for determining each level. For example, lets look at the l quantum number. if l=2, then we know n=3 because l=0,1,..n-1, meaning that n-1=2 meaning that n=3. This type of relationship is how mathematical...

ramayyala1G

Orbitals and subshell are not the same thing. It is asking you to find the number of orbitals within the subshell. So lets look at (a). it gives you n= 5 and l=2. If n=5 you know it is on the 5th energy level and l=2 means that is it on the d-block hence 5d is the subshell notation. We know l=2 corr...

ramayyala1G

The way I think about it is that if you look at the periodic table and lets use the p-block for the sake of this example. If you count starting at Boron all the way to Neon, then you count six elements in that row of the p-block meaning that their are 6 electrons possible in each p-block row. From t...

ramayyala1G

It really just depends on what is given to you in the problem. Some problems will give you the threshold energy. Some will not and in these types of problems, you will have to solve them. Meaning using the equation Lavelle gave to us in class, Energy of the photon- threshold energy= kinetic energy o...

ramayyala1G

I meant can you use a combustion reaction to find the empirical formula of a compound that does not contain oxygen? Or will oxygen always be present in the final empirical formula? Well yes, there are some compounds that react with Oxygen that they themselves do not contain oxygen within. Combustio...

ramayyala1G

I mean from the way Lavelle made it out to be in class, he just said that we use nanometers just to make it easier to say but it truly doesn't make a difference whether you use meters or nanometers would be my guess unless they specify in the problem to use one or the other.

ramayyala1G

Adding on to that, unless the specify what type of unit they want you to use, I am pretty sure you are free to choose then. Its usually best to stick with the units given in the problem unless told otherwise.

ramayyala1G

I understand what discrete mean but when he was talking about variables being quantized, Lavelle made it out to be something different. My understanding of quantized is that a variable that is quantized is discrete because the act of quantization makes variables or values discrete. Is this correct o...

ramayyala1G

C is correct because the change in an electric field is depends on the frequency of electromagnetic radiation. As a result, if the electromagnetic radiation has a low frequency, then it will create a small area of electric field and if the electromagnetic radiation has a high frequency, then it will...

ramayyala1G

So energy of radiation for the photons increases with an increase in its frequency, meaning the photons with higher frequencies will have higher energy of radiations.

CHEMISTRY COMMUNITY

Search found 31 matches

Re: Strength of Acid and Bases

Re: Amphoteric Oxides

Re: Strong or weak acids/ bases

Re: No Proton Transferred? HW Problem

Re: HW: 12.17

Re: 12.47

Re: 12.3a

Re: Polar Covalent vs. Unequally Shared

Re: Polar Vs. Non-Polar

Re: In Class Example Between LiF and CsF

Re: Logic behind Sigma and Pi bonds?

Re: shape of water

Re: Bond Angle

Re: 3.5 b) [ENDORSED]

Re: Midterm Question

Re: d block electron configuration

Re: 5a,c ; 19b,e ; 21d

Re: Valence electrons

Re: 2.51

Re: Different d and f orbitals

Re: Homework Problem 2.55

Re: n, l, ml (relates to 2.19)

Re: 2.27 [ENDORSED]

Re: 2.25

Re: Threshold Energy [ENDORSED]

Re: Combustion Reaction [ENDORSED]

Re: Units for wavelengths [ENDORSED]

Re: HW 1.7 (using nm vs pm)

Re: Quantized v. Discrete

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Re: HW ch1 question 5