CHEMISTRY COMMUNITY

Kara Justeson 1B

is this an exception to the general trend? Because I thought more electronegative atoms formed stronger acids.

Kara Justeson 1B

In response to the question above asking when it's ok to have less than 8 electrons, I think you just have to look at the formal charge and see what makes it the closest to neutral. I'm not completely sure though.

Kara Justeson 1B

I think a dipole moment is when there is an uneven sharing of the charges between the atoms. It relates to the partial negatives and partial positives on the atoms due to electronegativity differences. For example in H20 the Hydrogens have a partial positive and the Oxygen has a partial negative whi...

Kara Justeson 1B

Yes, Bronstead Acid is a H+ donor, while a Bronstead base is a H+ acceptor. Lewis Acid acid accepts the electron pair while the Lewis base donates the electron pair. I think the difference is just in the way they define the exchange.

Kara Justeson 1B

does this mean that it could have an s and a pz but not the px or py (like h2)? would the orbitals not go in order?

Kara Justeson 1B

I might be wrong, but I thought we didn't have to know how to tell the difference for this class. Based off what I understood from lecture I think we were just supposed to know that both types have four ligands.

Kara Justeson 1B

I think it has to do with different ways scientists classified acids and bases. I think they're just alternate ways to define them based on their properties.

Kara Justeson 1B

For this you would look at the difference in their electronegativities. If the bond is classified as covalent based on the electronegativity difference, but it has a high difference thats closer to the measure for ionic bonds, it's more likely to be polar covalent. You can tell it's ionic if the dif...

Kara Justeson 1B

I think with how you're asking why it doesn't just become a cation, it's because a radical is still a neutral atom (it has no charge since the protons=neutrons). So if it gained or lost an electron, it would become an ion. So it needs the presence of another (or multiple) atoms to pair it's single e...

Kara Justeson 1B

I'm not completely sure, but I think with the expanded octet it can hold up to as many electrons as the largest orbital of that element. For example, if it had a 3d subshell, since it has a d orbital it should be able to hold up to 10 electrons in the expanded octet.

Kara Justeson 1B

In response to the question right above this one, the formal charge also lets you know which structure would be correct since there as sometimes multiple ways you could draw the structure. Since the correct structure is the one thats the most stable (or with the formal charge they give you in that i...

Kara Justeson 1B

Just like was said above, you remove the outermost electrons because they are furthest from the nucleus and therefore they have the least amount of pull. Since it's the furthest out, it's the most loosely bound. That would make them the easiest to remove.

Kara Justeson 1B

I think when you're trying to determine whether a bond is ionic or covalent, you look at the electronegativity difference between the 2 atoms. If the difference is greater than 2 its ionic and if its less than 1.5 its covalent. You would find the electronegativity values on a chart in the book. I ho...

Kara Justeson 1B

the concept of a radical is that it is any atom that has an unpaired valence electron, but I'm not sure how we use them.

Kara Justeson 1B

For electrons in the s orbital, they're less shielded than electrons in the p-orbital and therefore the s orbital would have a higher Zeff value. Since Zeff is the positive charge the electron experiences, the less shielding and closer they are to the nucleus, the higher their zeff will be. So, I th...

Kara Justeson 1B

Since all of these ions have the same configuration which would be the configuration of Ar (they're isoelectronic), you would order them based on the number of protons they have. Since p has the fewest number of protons, it would pull the electrons the least and therefore have the largest ionic radi...

Kara Justeson 1B

I think for Ag, its because a fully filled or half filled d orbital is more stable, so it will try to be at either 5 or 10 electrons if possible. However, I'm not completely sure if it would then fill the 4d before the 5s or if it fills in the normal order but then transfers the electron to the 4d o...

Kara Justeson 1B

I think like the person who posted before me that the reason Tungsten isn't the same as Chromium is because Chromium is one of the two exceptions mentioned in lecture. So Tungsten should be following the normal pattern since Chromium is the one that is unusual.

Kara Justeson 1B

I believe for this part it's because they give you the angular momentum quantum # (l). Since they told you l=2, like you said you know it would be the d subshell. Because they told you l=2 you're only looking at that particular subshell not including the s or p.

Kara Justeson 1B

I might be wrong, but if I understand this correctly, the f block shown on the periodic table is inserted in the d block following Ba. Since Tungsten occurs after this block of elements, the f configuration would have to be considered.

Kara Justeson 1B

Since the energy we found in part b was Joules per molecule, you would multiply it by avogadro's number (which gives the number of molecules in a mol) in order to convert the energy to the number of joules per mol.

Kara Justeson 1B

I might be wrong but I think the equation used for this problem was just E=hv. In part a you would find the frequency based on the given wavelength, and in part b, you would use the frequency you found in part a and just plug it into the equation E=hv.

Kara Justeson 1B

for reference the problem says: in the uv spectrum of atomic hydrogen, a line is observed at 102.6nm. Determine the values of n for the initial and final energy levels of the electron during the emission of energy that leads to this spectral line. I understand how you find n=3 as being one of the en...

Kara Justeson 1B

You would use the constant given where 1 ev= 1.602x10^-19 J

Kara Justeson 1B

I think for that part you have to use the equation "Ephoton = Ek + work function" based on the correct answer. But I'm also a little confused about this equation and when to use it in general.

Kara Justeson 1B

The equation is c=hv (speed=wavelength x frequency). Since c (speed) is a constant if wavelength decreased, frequency would have to increase in order for the constant c to remain the same (3.00 x 10^8). Essentially, the wavelength and frequency have to equal the constant c when they're multiplied to...

Kara Justeson 1B

I think you have to go through celsius first, but you can do it all in one step. So you could do (F-32)x (5/9) +273.15 to convert to Kelvin.

Kara Justeson 1B

For the molecular and empirical formulas, if you only had the molecular structure (i think you're talking about the 3d pictures with different colors representing different atoms), you could count the number of each type of atom represented and use that to directly write the molecular formula (one c...

Kara Justeson 1B

The empirical formula would be the smallest ratio of the elements. For example if the molecular formula was C4H10, the empirical formula would be C2H5 (divided by a ratio of 2). Whereas the molecular formula tells you how many atoms are in that compound.

Kara Justeson 1B

I believe the 2 in 2Na is acting as a coefficient, so you would have 2 mols of Na whereas Na2 would change the structure of the atom. Na2 would be 2 Na bonded together while 2Na is still an unbound Na but in with a stochiometric coefficient so the ratios allow the chemical reaction to be balanced.

Kara Justeson 1B

Also since we know E=hv, since h is a constant if v(the frequency) decreases then E would decrease so D) is not correct. Going off the other equations we know we can also see that answers A) and B) don't represent the correct relationships between the terms. For A) the speed would not decrease becau...

CHEMISTRY COMMUNITY

Search found 31 matches

Re: HI or HCl: stronger acid

Re: Central atom and octet rule?

Re: Dipole Moment understanding

Re: Bronsted vs Lewis Acids and Bases

Re: Hybrid Orbitals

Re: 4 ligands shape?

Re: Acids/Bases and Lewis Acids/Bases

Re: Difference between polar covalent and ionic bond?

Re: Single electron

Re: expanded octets

Re: Formula Provided

Re: Configurations

Re: How to tell which elements will be most likely to form a covalent bond

Re: Radicals

Re: Zeff HW 2.37

Re: Increasing Ionic radius

Re: Homework 2.43 [ENDORSED]

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Re: 2.17 homework problem

Re: Homework 2.43 [ENDORSED]

Re: 1.55 part c

Re: 1.55 part b

Re: Problem 1.15 Textbook

Re: eV to Joules [ENDORSED]

Re: Homework Problem #33

Re: Wavelength and frequency proportions [ENDORSED]

Re: conversion from Fahrenheit to kelvin

Re: chemical formula [ENDORSED]

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Re: chemical formula [ENDORSED]

Re: HW chapter 1 question 3