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Review my work?

  1. Apr 19, 2005 #1


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    Okay I did my work but if someone would be so kind as to look at it and see if I am understanding.
    1. Explain why you would expect a BeF2 molecule to be linear but an SF2 molecule to be angular?
    BeF2 forms an ionic bond with 2 single bonds. Since Be is in group IIA it forms two sp hybrid orbitals. The farthest away the pairs can be is 180 o angle, making it linear. SF2 forms two covalent bonds with two F atoms. Having four pairs of electrons around the S atom the farthest away they can be is in an angular shape.

    2a) How would you designate the hybrid orbitals formed by "mixing" one d, one s and two p orbitals?
    a) When mixing one d orbital, one s orbital and 2 p orbitals you get dsp2.
    b) How many of the hybrid orbitals would be formed by the mixing?
    b) The number you put in is the number you get as a result. So in this case we put in 4 orbitals we then get 4 hybrid orbitals.

    3. Explain why C20H40 is a solid at 25degcel, while C4H8 is a gas at 25degcel?
    39. C20H40 is a solid at 25o C because has more electrons. With more electrons you get more forces that can hold the lattice pattern together. C4H8 is a gas at 25o C because the bonds are weak and that gives this compound a low boiling temp.

    4.Arrange the following atoms or ions in order of increasing radius:
    Cl, S2-, K, K+, O
    if an explanation for teh position of S2- in relation to the atom or ion in front and behind it.
    OK I have:31.
    O, S2-, K+, Cl ,K
    increasing radius

    S2- is smaller than K+ in this case because it has a configuration the same as Ar, a noble gas. Moving horizontally in the periodic table the radius decreases in size.
    S2- is bigger than Cl because?
    If someone would look over my answers and see if i am correct or even close.
    Thank you
  2. jcsd
  3. Apr 19, 2005 #2


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    2 is entirely correct.1 is okay.Indeed the nonbonding pairs distort the linear structure.At 3,there's a connection between the molar mass and the the # of atoms in the hydro-carbide.

    4.The order should be


    increasing ionic/atomic radius.

    1.The # of electrons and the # of shells are the main criteria.
    2.For isoelectronic configurations,the largest radius corresponds to the smaller nuclear charge.

  4. Jun 14, 2005 #3

    Sorry about that, I should read better before posting.. I understand it now
    Last edited: Jun 14, 2005
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