1031 Exchange with spouse

[William Lamping]

I have received an offer on my rental property from the county. They want to improve the adjacent roadway and my place is in the way. I have owned it for 15years and its been a rental for the past 11 consecutive years. The offer is 240,000, I owe 87,000. I would like to buy my wife's 1st house, which has been vacant since we moved out in 2017 when we bought our current home. She bought it in 2008 prior to us meeting and I have never had financial interest in it(I'm not on the mortgage). Her house is valued at 250,000 with a mortgage of 100,000. If I were to do a 1031 exchange and buy her property for 250,000 using the proceeds of my sale (240k-87k) plus cash, how would she be taxed on the proceeds from here sale(250k sale price-100k mortgage)? 

Thanks

-Bill