(1) There are exempt from the tax imposed by this chapter all sales for which the consideration is a voucher issued under the Special Supplemental Food Program for Women, Infants and Children (42 U.S.C. § 1786), and any subsequent federal legislation. If consideration other than such vouchers is used in any sale, that portion of such sale shall be fully taxable.
(2) If not required by federal law, this exemption shall not be implemented and shall have no effect.