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                                                                     EXHIBIT 4.7




                               FIRST AMENDMENT TO
                                 CHEMFIRST, INC.
                       401(k) AND EMPLOYEE STOCK OWNERSHIP PLAN AND TRUST

         THIS AMENDMENT, effective JANUARY 1, 1998, by and between CHEMFIRST,
INC., a Business Corporation, having its principal office in Jackson,
Mississippi (hereinafter referred to as "Employer"), and CHARLES SCHWAB TRUST
COMPANY (hereinafter sometimes referred to as "Trustee");

                                R E C I T A L S:

         A. WHEREAS, the Employer has previously established the ChemFirst, Inc.
401(k) and Employee Stock Ownership Plan and Trust ("Plan and Trust") for the
benefit of those employees who qualify thereunder and for their beneficiaries;
and

         B. WHEREAS, the Employer desires to amend the Plan and Trust to (i)
clarify the definition of Eligible Employee and (ii) eliminate the service
requirement for purposes of eligibility and entry in the Plan;

         NOW, THEREFORE, pursuant to Section 10.01 of the Plan and Trust, the
following amendment is hereby made and shall be effective as of JANUARY 1, 1998:

1.       SECTION 1.13 OF THE PLAN IS AMENDED AS UNDERLINED TO READ AS FOLLOWS:

1.13     Eligible Employee Classification

         An Eligible Employee Classification is a classification of Employees,
         the members of which are eligible to participate in the Plan. All
         Employees who are classified as "Regular Employees" are eligible to
         participate in the Plan.

2.       SECTION 1.15 OF THE PLAN IS AMENDED AS UNDERLINED TO READ AS FOLLOWS:

1.15     Employee

         (a)      In General

                  An Employee is any person who is employed by the Employer or a
                  Participating Employer.

         (b)      Leased Employee

                  A Leased Employee means any person who, pursuant to an
                  agreement between the Employer or any Related Employer
                  ("Recipient Employer") and any other person ("leasing
                  organization"), has performed services for the Recipient
                  Employer on a substantially full-time basis for a period of at
                  least one year and such services are performed under the
                  primary direction or control of the Recipient Employer.

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                  Any Leased Employee will be treated as an Employee of the
                  Recipient Employer; however, contributions or benefits
                  provided by the leasing organization which are attributable to
                  the services performed for the Recipient Employer will be
                  treated as provided by the Recipient Employer. If all Leased
                  Employees constitute less than 20% of the Employer's
                  non-highly-compensated work force within the meaning of Code
                  Section 414(n)(1)(C)(ii), then the preceding sentence will not
                  apply to any Leased Employee if such Employee is covered by a
                  money purchase pension plan ("Safe Harbor Plan") which
                  provides: (1) a nonintegrated employer contribution rate of at
                  least 10% of compensation, (2) immediate participation, and
                  (3) full and immediate vesting.

                  Years of Eligibility Service for purposes of eligibility to
                  participate in the Plan and Years of Vesting Service for
                  purposes of determining a Participant's Vested Percentage
                  include service by an Employee as a Leased Employee.

         (c)      Regular Employee

                  Regular Employee is an Employee (whether full time or part
                  time) hired to fill a specific position on a permanent basis
                  and for whom the Employer annually budgets compensation and
                  benefits.

3.       SECTION 1.27 OF THE PLAN IS AMENDED IN ITS ENTIRETY TO READ AS FOLLOWS:

1.27     One Year Break-in-Service

         One Year Break-in-Service means any 365-day period following a
         Participant's Date of Termination in which an Employee does not
         complete at least one (1) Hour of Service.

4.       SECTION 1.45 OF THE PLAN IS AMENDED IN ITS ENTIRETY TO READ AS FOLLOWS:

1.45     Year of Service

         (a)      Crediting Years of Service. Years of Service are determined
                  using the Elapsed Time Method as specified in this Section.

                  (1)      Elapsed Time Method. The Elapsed Time Method shall be
                           used to compute Years of Eligibility Service and
                           Years of Vesting Service for all Regular Employees.

                           Under the Elapsed Time Method, Years of Service are
                           based upon an Employee's Elapsed Time of employment
                           irrespective of the number of hours actually worked
                           during such period; a Year of Service (including a
                           fraction thereof) will be credited for each completed
                           365 days of Elapsed Time which need not be
                           consecutive. The following terms are used in
                           determining Years of Service under the Elapsed Time
                           Method:

                           o        Date of Severance (Termination) - means the
                                    earlier of (A) the actual date an Employee
                                    resigns, is discharged, dies or retires, or
                                    (B) the first anniversary of the date an
                                    Employee is absent from work (with or
                                    without pay) for any other reason, e.g.,
                                    disability, vacation, leave of absence,
                                    layoff, etc.

                           o        Elapsed Time - means the total period of
                                    service which has elapsed between a
                                    Participant's Employment Commencement Date
                                    and Date of Termination including Periods of
                                    Severance where a One Year Break-in-Service
                                    does not occur.


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                           o        Employment Commencement Date - means the
                                    date an Employee first performs one Hour of
                                    Service for the Employer.

                           o        One Year Break-in-Service - means any
                                    365-day period following an Employee's Date
                                    of Termination as defined above in which the
                                    Employee does not have at least one Hour of
                                    Service.

                           o        Period of Severance - is the time between
                                    the actual Date of Severance as defined
                                    above and the subsequent date, if any, on
                                    which the Employee performs an Hour of
                                    Service.

                           All periods of employment will be aggregated
                           including Periods of Severance unless there is a One
                           Year Break-in-Service.

                  Years of Eligibility Service for purposes of determining
                  eligibility to participate in the Plan and Years of Vesting
                  Service for purposes of determining a Participant's Vested
                  Percentage include service with any organization which is a
                  Related Employer with respect to the Employer.

         (b)      For Eligibility Purposes. All Regular Employees who have
                  completed at least one (1) hour of service shall be eligible
                  to participate in the Plan.

         (c)      For Vesting Purposes

                  Years of Service for purposes of computing a Participant's
                  Vested Percentage are referred to as Years of Vesting Service
                  and are determined using the Elapsed Time Method. For purposes
                  of determining an Employee's Years of Vesting Service, an
                  Employee shall receive credit for the aggregate of all time
                  periods commencing on an Employee's Employment Commencement
                  Date, including the Re-Employment Commencement Date, and
                  ending on the date a Break-in-Service begins. An Employee also
                  shall receive credit for any Period of Severance of less than
                  365 days. A Year of Vesting Service (including a fraction
                  thereof) will be credited for each completed 365 days of
                  Elapsed Time which need not be consecutive. In computing an
                  Employee's Years of Vesting Service, the following rules shall
                  apply:

                  (i)      Service shall be disregarded in computing a
                           Participant's Years of Vesting Service under the Plan
                           for Plan Years beginning prior to March 1, 1985, for
                           which the Employee was eligible to make basic
                           contributions (after-tax contributions) but declined
                           to make any such contributions to the Plan, if such
                           period occurred prior to his initial date of
                           participation in the Plan.

                  (ii)     Service shall be disregarded in computing a
                           Participant's Years of Vesting Service for Plan Years
                           beginning on or after March 1, 1985, but before
                           October 1, 1993, for which the Employee was eligible
                           to direct the Employer to make Salary Deferral
                           Contributions on his behalf but declined to direct
                           the Employer to make any such contributions to the
                           Plan; and if such period occurred prior to his
                           initial date of participation in the Plan.

                  (iii)    Service prior to July 1, 1974, shall be disregarded
                           in computing a Participant's Years of Vesting
                           Service.

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         (d)      Related Employers

                  Years of Eligibility Service for purposes of determining
                  eligibility to participate in the Plan and Years of Vesting
                  Service for purposes of determining a Participant's Vested
                  Percentage include service with any organization which is a
                  Related Employer with respect to the Employer.

         (e)      Loss of Service

                  If a Participant who is zero percent (0%) vested terminates
                  employment and incurs at least 5 consecutive One Year
                  Breaks-in-Service, he or she will lose all prior Eligibility
                  Service and Vesting Service.

         (f)      Change in Computation Method

                  With respect to the Employee Stock Ownership Plan Accounts
                  merged hereunder, for purposes of determining a Participant's
                  Years of Vesting Service in those Accounts as of December 31,
                  1996, the method used to calculate Years of Vesting Service
                  shall be the method described in Section 2.14 of the First
                  Mississippi Corporation Employee Stock Ownership Plan prior to
                  August 1, 1996, or in this Section 1.45, whichever will result
                  in the higher vested percentage.

5.       SECTION 2.01 OF THE PLAN IS AMENDED IN ITS ENTIRETY TO READ AS FOLLOWS:

2.01     Participation

         All Regular Employees are eligible to participate in the Plan on the
         Regular Employee's Employment Commencement Date.

         Employees not eligible to participate in the Plan are:

         o        Collective Bargaining Employees. Each Employee who is a member
                  of a collective bargaining unit shall not be eligible to
                  participate in this Plan unless the collective bargaining
                  agreement provides otherwise. An Employee is a member of a
                  collective bargaining unit if the Employee is included in a
                  unit of Employees covered by an agreement which the Secretary
                  of Labor finds to be a collective bargaining agreement between
                  Employee representatives and one or more employers if there is
                  evidence that retirement benefits were the subject of good
                  faith bargaining between the Employee representatives and the
                  employer or employers. The term "Employee representatives"
                  does not include an organization of which more than one-half
                  (1/2) the members are owners, officers, or executives of the
                  Employer.

         o        Leased Employees.

         An Employee who is otherwise eligible to participate may irrevocably
         elect not to participate in the Plan. Any election under this paragraph
         must be in writing and according to guidelines established by the Plan
         Administrator.

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         IN WITNESS WHEREOF, this instrument has been executed by the duly
authorized and empowered officers of the Employer, this 31st day of December,
1998.

                                 EMPLOYER:

                                 CHEMFIRST, INC.



                                 By:  /s/ James R. Lewis
                                     -------------------------------------------

                                 TRUSTEE:

                                 CHARLES SCHWAB TRUST COMPANY



                                 By:  /s/ K. Mason
                                     -------------------------------------------
