The State Bond Commission shall authorize the issuance of bonds of the state in one or more series in accordance with section 3-20 and in a principal amount necessary to carry out the purposes of this chapter, but not in excess of an aggregate amount of thirteen million dollars. All of said bonds shall be payable at such place or places as may be determined by the Treasurer pursuant to section 3-19 and shall bear such date or dates, mature at such time or times, not exceeding five years from their respective dates, bear interest at such rate or different or varying rates and be payable at such time or times, be in such denominations, with or without interest coupons attached, carry such registration and transfer privileges, be payable in such medium of payment and be subject to such terms of redemption, with or without premium as, irrespective of the provisions of said section 3-20, may be provided by the authorization of the State Bond Commission or fixed in accordance therewith. The proceeds of the sale of such bonds, together with the premium and interest on sale, if any, shall be deposited in the Housing Purchase and Rehabilitation Fund created under section 8-285. Such bonds shall be general obligations of the state and the full faith and credit of the state of Connecticut are pledged for the payment of the principal and interest of such bonds as the same become due. Accordingly, and as part of the contract of the state with the holders of such bonds, appropriation of all amounts necessary for punctual payment of such principal and interest is hereby made, and the Treasurer shall pay such principal and interest as the same become due. Net earnings on investment or reinvestment of proceeds, accrued interest and premiums on the issuance of such bonds, after payment therefrom of expenses incurred by the Treasurer or State Bond Commission in connection with their issuance, shall be deposited in the General Fund of the state.