Mama hen hatched chicks on her own, where did she go?

[Kfarms2016]

We found one of our hens with two chicks yesterday morning. Had no idea she was on a nest! We found her sitting on her nest near our house with two hatched babies. When we checked on her this morning all her eggs appeared hatched (10 eggs!) and she was gone except for one live chick was still near the nest. We have no idea where mama went and the other babies. It was also pouring like crazy for a couple hours this morning so we rescued baby chick. We been walking all over our property trying to find signs of them but no luck yet. The one baby chick that was left behind is set up with a heat lamp, food and water.

 

[50-45-1]

I'm a little confused by your post.
You found a hen yasterday with 2 chicks, but this morning she had 10 eggs hatched??
It kind of sounds like she had a nest in an unsecure location and she and 1 or 9 chicks have gone missing.
For a hen to willingly leave 1 chick behind is unusual. She may have been startled by something and left hurriedly.
She may show up.
But also possible she was taken by a preditor
I hope she returns.
If not I would recommend you purchase 2 or 3 chicks close to the same age as the one you have, so he has friends to be raised with. Chickens are flock animals
Good luck!