1. F

    Is there any change in mass as the electron changes energy levels.

    Does anything happen to the electron, as it changes energy levels, does its mass increase, or decrease, or velocity speed up, or slow down.? The electron will speed up when its away from the nucleus, when its in a higher shell like shell level 3. But is there anything like a visible sign that...
  2. F

    Is it known to science why electron energy levels change, as atoms become molecules,

    Is it known to science why electron energy levels change, as atoms become molecules, or why electron voltage requirement changes when the electron is from the nucleus in higher shell levels. So can it just he observed that electrons need a certain electron voltage to move to higher shell...
  3. J

    How many fluorine atoms are present in 10 moles of SF6 (Sulfur Hexafluoride)

    I know I have to use avogadro number. The correct answer is 4 * 10 ^ 25 but how do you get that answer. Please help.
  4. G

    Atoms and Ions and Stability

    Hello Please disapprove me if I am wrong (which I think I am ) If an atom is stable when the electrons = protons, I assume Na is stable but Na^+ is also stable because it fulfilled the octet rule even though it has 10 electron and 11 protons ? " I haven't learned about Stability yet, so...
  5. C

    How many carbon atoms

    When 0.0112 dm3 of an organic compound Y was burnt in excess oxygen, 0.83 g of carbon dioxide was formed at stp. How many carbon atoms are there in one molecule of Y? I'm not sure what to do
  6. S

    Given mass and Atoms find Unknown element

    5.44 grams of an element contains 3.24x10^22 atoms which element is this? I know avogadros # is 6.022x10^23 Not really sure what to do, I have been in my university chemistry class for over a month now. This is not a test question or an assignment, just a practice sheet worth no marks.
  7. M

    Converting moles to atoms vice versa

    This is more of a question about the mathmatics, specifically involving getting the exponents of the answer after dividing (converting from atoms to moles). I understand that when I'm given a problem such as: (1) Convert the number of moles of potassium containing 8.91 * 10^25 atoms. 8.91...
  8. K

    Determining number of atoms?

    Had these 2 questions for chemistry homework and it is really frustrating me. Here is the information: The radius of an atom of gold (Au) is about 1.35 Angstroms, How many gold atoms would have to be lined up to span 9.0mm ? If the atom is assumed to be a sphere, what is the volume in cm^3 of a...
  9. M

    Simple # of Atoms Calculation

    Hi guys, Just a bit of background on me: I completed chemistry in high school and did pretty good, but then when I went to university I didn't take any chem courses for a year. This coming fall I'm going to be enrolled in an introductory university chem course, so I'm doing some prep work now...
  10. S

    Hybrdization of atoms that do not follow octet rule

    So far I am clear on how hybridization works for "most" atoms. But some atoms do not obey the octet rule... Some atoms have more than an octet of electrons, in which case it's either spppd or spppdd hybridization. That I understand. Some atoms though have fewer than an octet of electrons...
  11. C

    structure of atoms help please

    An atom of an isotope of an element of atomic number 7 and mass number 15 has? :confused: im not that great at chem but im guessing that the answer is 7 protons? can someone agree or disagree an maybe say why? thanks:)