as Executor of my mother estate is it legal to pay electric, gas, and water bills for her home from the estate money

Yes, the estate is liable for the costs of maintaining a house owned by the estate.  I'm assuming that you have been appointed executor by the court, which gives you the legal authority to open an estate bank account, sell the house, etc.  If the estate has no funds to pay the bills, the heirs are not responsible to pay them out of their own funds. You may decide to invest some of your own money into the house for renovations to help it sell.  In that case, I would come up with a written agreement to ensure that you will get your money back when the house sells.  If the house is worth less that it will cost to pay these bills, the other choice is to not pay them and let the creditors file claims against the house and/or try to sell the house as is for less money.  Again, heirs are not personally liable.