Genesis 12:10-20 is clearly an exodus story, but Jerome Walsh ( Style and Structure in Biblical Hebrew Narrative ) points out that the exodus story is told chiastically.  The following is a modified version of his outline:

A. Abram in Egypt to escape famine, 12:10

B. Sarai taken to harem, 12:11-15 (Sarai poses as sister)

C. Pharaoh treats Abram well, 12:16

C’. Yahweh strikes Pharaoh with plagues, 12:17-19a

B’. Pharaoh returns Sarai, 12:19b (“She is my sister”)

A’. Pharaoh expels Abram, 12:20

At the center of the structure is another chiasm in the list of goods that Pharaoh gifts to Abram:

A. Flocks and herds

B. Jackasses

C. Men servants

C’. Female servants

B’. Jenny asses

A’. Camels

After these six gifts, Pharaoh gives Abram a seventh, his bride, the new Eve, mother of the living.

And, the longer section of the overall chiasm (vv. 11-14) is also arranged in a reverse symmetry:

A. Approaching Egypt; “You are beautiful,” v 11

B. They will kill me, v 12

C. Say you are my sister, v 13a

B’. That I may live, v 13b

A’. Arrival in Egypt; Sarai is very beautiful, v 14