[imari]

I had two questions that I answered but I don't know if they are right.

First, "Before the public became serious about pollution, it was common to improve the performance of gasoline by the addition of lead compounds. A particular 100-octane aviation gasoline used 1.00 cm3 of tetraethyl lead, (C2H5)4Pb, of density 1.66 g/cm3, per liter of product. How many grams of ethyl chloride are needed to make enough tetraethyl lead for 1.00 L of gasoline?"

4(C2H5Cl) + 4(NaPb) --> (C2H5)4Pb + 4NaCl + 3Pb
    g?                               1.66g

To find how many grams of (C2H5)4Pb I needed, i multiplied 1.00 cm3 with 1.66 g/cm3 to get 1.66 g/l (C2H5)4Pb.

Then I divided 1.66g (C2H5)4Pb by 323 g/mol (C2H5)4Pb to get .005 mol (C2H5)4Pb.

Then I multiplied .005 mol by 4 because of the 4:1 ratio to get .02 mol C2H5Cl

And last I multiplied .02 mol by 64.6 g/mol to get 1.29g C2H5Cl

Is that right?


Second, I had to write several lewis structures but there are a few that I am not sure if I did right either.

a) C2HCL   H-C triple bond C-Cl

b) C2H6O  I had originally put   H H       but when I looked online, it had the O in
                                      H-C-C-O-H  between the carbons or the OH on top of
                                         H H           one of the carbons instead of on the
                                                        outside. Does it matter?



c) C2H4O  I put  H H           but online, I saw it with the double bond between the
                       C=C-O-H    C and the O like   H H
                       H                                   H-C-C=O
                                                               H
     Is the way I drew it wrong and how was I supposed to know that the double   
     bond is between the C and the O and not between the carbons?

[Borek]

In the first question you are close, but it looks to me like you are rounding intermediate results, in effect your final result is about 3% off.