CHEMISTRY COMMUNITY

Maria Zamarripa 1L

Elements that are in period 3 and beyond have the capacity to have an expanded octet. So if you have extra electrons, these elements would be able to hold more than 8 electrons.

Maria Zamarripa 1L

If you are checking for formal charge and actually plugging into the equation then you should count bonds as two because you will be multiplying by 1/2 anyway, but if you are just counting them and subtracting from the number of valence electrons it has then only count the bonds as having one electr...

Maria Zamarripa 1L

All atoms have to follow the octet rule unless they are able to have an expanded octet. Elements in period 3 or after are able to hold more than 8 electrons.

Maria Zamarripa 1L

The least electronegative atom would go in the center but Hydrogen I know for sure can never be the center atom.

Maria Zamarripa 1L

The equation for the formal charge is, formal charge = V - (L+1/2(B)) V= # of valence electron of the element, L= # of lone pairs surrounding the atom (count each electron), B= bonded pairs (count each electron)

Maria Zamarripa 1L

Any atom has the ability to form multiple bonds. you just have to keep in mind that not all atoms can have expanded orbitals.

Maria Zamarripa 1L

N has less valence electrons than Cl and is more willing to give up its electrons than Cl.

Maria Zamarripa 1L

So basically and acid would be an electron acceptor and a base is an electron donor.

Maria Zamarripa 1L

so the equation for formal charge is
formal charge= v-(L+(1/2(B))
v= # of valence electrons
L= # of Lone pairs
B= # of Bonded pairs

Maria Zamarripa 1L

I believe that once you convert mL to L at the beginning of the problem, you should keep it as Liters at the end of the problem.

Maria Zamarripa 1L

I know it's kind of early but does anyone want to start a study group to start studying for the final?

Maria Zamarripa 1L

Thank you for the clarification, just one more additional question, how do you figure out how many sig figs you will be needing at the beginning of the problem?

Maria Zamarripa 1L

conceptually, I think it's because since the wavelength is longer there are fewer cycles per second so it is moving slower and has less energy.

Maria Zamarripa 1L

When doing a calculation and the number is really long on the calculator, how many places do we round to? and does it affect sig figs?

Maria Zamarripa 1L

do we have to apply the sig fig rules at each step of the problem or only at the last step?

Maria Zamarripa 1L

I also have a question pertaining to this question, in the answer manual it said n2=7. How did they solve to get that?

Maria Zamarripa 1L

I believe that everything does have wavelike properties.

Maria Zamarripa 1L

It has to be at least the amount of energy of the threshold if not more.

Maria Zamarripa 1L

the empirical is the ratio rather than the actual so you would just simplify as much as possible.

Maria Zamarripa 1L

i believe that Theoretical is the ration of the elements and the actual is the actual amount

Maria Zamarripa 1L

When: at the end of solving the problem.

Maria Zamarripa 1L

If it gives you are given milliliters then you change it to liters and I believe you keep the final answer in Liters too.

Maria Zamarripa 1L

Do we have to keep sig figs in mind in all of the questions we solve?

Maria Zamarripa 1L

Will there be questions about new topics we learn in week 4?

Maria Zamarripa 1L

You must have whole numbers because you can not just have a part of an atom.

Maria Zamarripa 1L

In order to get the best answer/result having both high precision and high accuracy are important.

Maria Zamarripa 1L

I think it is okay to use 16. I usually just use it because it is on the periodic table on the front of the textbook.

Maria Zamarripa 1L

Precision is how close the measurements are to one another and accuracy is how close the measurements are to the true value.

Maria Zamarripa 1L

So just for clarification, Avogadro's number is only used when you're given moles?

Maria Zamarripa 1L

I think that it doesn't matter too much which one you use. I think I typically see mol.

CHEMISTRY COMMUNITY

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