Will I be able to get into a good college with a D in chem?

Hey guys.. I just finished my Junior Year of High School with a cumulative GPA of 3.1. I just got my report card and am WICKED upset that I got a D in my Second Semester Chemistry course. My first semester I got a C. I am extremely concerned that colleges will decline my acceptance because of this grade... How serious of a situation am I in? Thanks...