Question

1. Because it was so late, we went home.
2. Because of its lateness, we went home.

(Is #2 grammatical?)

Answer 1

1. Because it was so late, we went home.
2. Because of its lateness, we went home.
3. Because of its too lateness, we went home.
(Is #2 or #3 grammatical?)

Answer 2

Use only #1 -- 2 and 3 aren't correct, as is.