Lewis structures are a simplified two dimensional "cartoon" of molecular structure that allow a knowledgeable user to predict the types of properties a particular substance may exhibit. However, prior research shows that many students fail to recognize these structure-property connections and are unable to decode the information contained in the structures, thus resulting in students' inability to use Lewis structures for their intended purposes. We have developed a survey instrument using responses from student interviews and open-ended questions from a previous research study to determine students' beliefs about the information that can be obtained from Lewis structures. The survey was found to be reliable and valid through multiple administrations to a total of 3203 students, including first- and second-semester general chemistry and organic chemistry students, junior/senior level undergraduate chemistry students, and graduate level chemistry students. We propose that this survey can be a useful informational tool for instructors for a wide range of courses where students' understanding of structure-function relationships is important. (Contains 4 figures and 2 tables.)