(a) The tax imposed by this chapter is the primary liability of the producer and, except as provided by Subsection (b) of this section, is a liability of the first purchaser and each subsequent purchaser. Failure of the first purchaser to pay the tax does not relieve the producer or a subsequent purchaser from liability for the tax. A purchaser of gas produced in the state shall satisfy himself that the tax on that gas has been or will be paid by the person liable for the tax.
(b) The first purchaser is not liable for the tax imposed by this chapter on gas for which the producer is required to pay the tax as provided by § 201.2041 of this code, unless the first purchaser purchases the gas for resale or resells the gas.