EXHIBIT 5








                                                   October 21, 1997






Board of Directors
Union Carbide Corporation
39 Old Ridgebury Road
Danbury, CT  06817-0001


            Re:  Registration Statement on Form S-8 for
                 1997 Stock Option Plan for Non-Employee
                 Directors of Union Carbide Corporation
                 ---------------------------------------

Dear Sirs:

            We are acting as counsel to Union  Carbide  Corporation,  a New York
Corporation ("Corporation"),  in connection with the preparation and filing of a
Registration  Statement  on Form S-8 (the  "Registration  Statement")  under the
Securities  Act of 1933, as amended,  ("Act") with the  Securities  and Exchange
Commission  ("Commission")  relating to the  registration  of 200,000  shares of
common stock, $1.00 par value per share (the "Common Stock"), of the Corporation
offered for sale pursuant to 1997 Stock Option Plan for  Non-Employee  Directors
of Union Carbide Corporation (the "Plan").

            In connection  with this opinion,  we have examined and are familiar
with originals or copies, certified or otherwise identified to our satisfaction,
of such  documents,  corporate  records,  certificates  of public  officials and
officers  of the  Corporation  and  such  other  instruments  as we have  deemed
necessary or appropriate as a basis for the opinions expressed below.






Board of Directors
 Union Carbide Corporation          -2-                    October 21, 1997


            For purposes of this opinion we have assumed the authenticity of all
documents  submitted  to us as  originals,  the  conformity  to originals of all
documents   submitted  to  us  as  certified  or  photostatic  copies,  and  the
authenticity  of the  originals of all documents  submitted to us as copies.  We
have also assumed the legal capacity of all natural persons,  the genuineness of
all  signatures on all  documents  examined by us, the authority of such persons
signing on behalf of the parties  thereto other than the Corporation and the due
authorization,  execution and delivery of all  documents by the parties  thereto
other  than the  Corporation.  As to certain  factual  matters  material  to the
opinion  expressed  herein,  we have relied to the extent we deemed  proper upon
representations,  warranties  and statements as to matters of officers and other
representatives  of the Corporation.  Our opinion  expressed below is subject to
the  qualification  that we express no opinion as to any law other than the laws
of the State of New York and the federal  laws of the United  States of America.
Without  limiting  the  foregoing,  we express no  opinion  with  respect to the
applicability  thereto or effect of municipal laws or the rules,  regulations or
orders of any municipal agencies within any such state.

            Based upon the foregoing, we are of the opinion that:

            1. The   Corporation  has  been   duly  organized  and   is  validly
existing under the laws of the State of New York.

            2. The Plan has been duly adopted by the  Board of  Directors of the
Corporation and approved by the shareholders of the Corporation.

            3. The  shares  of  Common  Stock of the  Corporation  to which  the
Registration  Statement  relates  have been duly  authorized  and  reserved  for
issuance  pursuant to the Plan and,  when issued and sold  pursuant to the Plan,
will be legally issued, fully paid and non-assessable.

            This opinion is limited to the specific issues addressed herein, and
no opinion may be inferred or implied  beyond that expressly  stated herein.  We
assume no  obligation to revise or  supplement  this opinion  should the present
laws of the  State of New  York or the  federal  laws of the  United  States  of
America be changed by legislative action, judicial decision or otherwise.

            We hereby  consent to the  filing of this  letter as an Exhibit 5 to
the Registration  Statement. In giving such consent, we do not admit that we are
in the category of persons whose consent is required  under Section 7 of the Act
or the rules and regulations of the Commission promulgated thereunder.






Board of Directors
 Union Carbide Corporation          -3-                    October 21, 1997


            This opinion is furnished  to you in  connection  with the filing of
the  Registration  Statement  and is  not  to be  used,  circulated,  quoted  or
otherwise relied upon for any other purpose.

                             Very truly yours,


                             KELLEY DRYE & WARREN LLP