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Homework Help: Please help me with my chemistry homework

  1. Nov 7, 2006 #1
    I Have two questions please please help I will greatfully appreciate it

    1.) Describe the process of how an ionic bond forms. You should discuss the types of atoms involved (metals or non-metals) as well as the electrons involved.

    2.) Describe the process of how a covalent bond forms. You should discuss the types of atoms involved (metals or non-metals) as well as the electrons involved.
  2. jcsd
  3. Nov 7, 2006 #2
    We don't do the questions, we help with them. Some effort on your part is required.

    To get you started, look into electronegativity. What does it measure? What can be determined by differences of electronegativity?
  4. Nov 7, 2006 #3
    I just noticed you double posted this. All future posts should be made in the Homework forum.
  5. Nov 8, 2006 #4
    I'm sorry all this is new to me I just joined yesterday Im terrible at chemistry and algebra. I didnt expect to be handed the answers I just asked for help... now i dont understand what does what measure? if i remember correctly ionic bonds are a bond in which one atom donates electrons to another atom.
  6. Nov 8, 2006 #5
    In a very crude sense, bonds come down to electronegativity, and the reason for bonds is to achieve a noble gas configuration. Fluorine only needs one more electron to achieve a noble gas configuration, so it will eagerly react with another molecule to achieve that. If it reacts with an atom or ion with a significant electronegativity difference, that other substance will effectively donate its electron, giving fluorine a full octet (i.e. noble gas configuration). A good example of this is HF, where H+ donates an electron and F- receives it. Both are now in a noble gas configuration. This bond is an ionic bond, and involves cations and anions (I'll let you determine which is which).

    Another type of bond, known as a covalent bond, forms when two (or more) substances are trying to obtain noble gas configurations but do not have a great electronegativity differential. When this is the case, neither atom can sufficiently pull the electron away from the other. The compromise (which defines a covalent bond) is that they share the electron. This is why you see elemental fluorine in a diatomic molecule, F2. Each shares an electron with the other, giving both a full octet. There are no cations or anions with covalent bonds, although one atom can pull more strongly than the other; this gets into polarity and dipole moments, which I presume you do not have to go into.

    This should get you started, although the questions ask for more than just this, so take it only as a starting point.
  7. Nov 8, 2006 #6
    Ionic bonds form when one atom donates electrons to another atom to have its outter energy level completely full. the farter to the left and down the periodic table you go the easier it is for electrons to be taken away from metals. the farther right and up you go on the table the more vigorous exchange of electons for non metals.

    Covalent bonds share electrons to become nobel gases, but because neither atom is able to take an electon from the other they share the electon and the same thing applies about metals and non metals.

    am i getting this correctly?
  8. Nov 10, 2006 #7
    Covalent bonds involve the sharing of electrons to gain a stable electron configuration.

    They do not become noble gases. (You are correct to think that the group 8 gases are inert, though.)

    I'm unsure if you've done electronegativity, but a covalent bond occurs when the electronegativity difference between the adjoined atoms is greater than zero but less than 1.7.
  9. Nov 10, 2006 #8
    Sorry I didn't reply to this sooner. For some reason, this thread did not show up to me as recently added to, so I only saw your post after calcnd replied.

    You're generally correct about ionic bonds, although I did not understand your last sentence. If by farther up and right (i.e. more electronegative) you mean the atoms become more competitive for electrons, then you're correct.

    As calcnd pointed out, covalent bonds do not become noble gases. Rather, each atom involved obtains a noble gas configuration. Note the (very important) difference. They have the same number of electrons as the next highest noble gas, but they maintain the same number of protons and neutrons as they did as atoms.

    Yes, atoms in covalent bonds share electrons, although be wary that they are often shared unequally. That is, the bond is polar. So, though the electrons in an F-F bond are shared equally, the electrons in an H-F bond tend toward the F.
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