Can I buy a 1031 property BEFORE I sell the other property?

[Pearce G.]

I have a parcel that has a house plus some adjacent vacant land that I have owned less than a year.  I subdivided and now have separate offers on the house and on the residual vacant land.  The sale of the vacant land is less money, is a cash offer, and will close sooner than the sale of the house.  The house is more money and will retain the original address and mortgage.  I won't pay off the mortgage and realize a profit until the sale of the house closes.

However, the sale of the vacant land will free up enough cash for a 1031 exchange.  I have already identified a property and am eager to get it under contract.

If I purchase a 1031 property BEFORE the previous property is sold, is it still a 1031 exchange?