Diversity in STEM (science, technology, engineering, and math) fields has become a prominent issue as it becomes clearer that many groups remain underrepresented in STEM careers. This work primarily has focused on women and underrepresented racial minorities in STEM communities. However, members of the lesbian, gay, bisexual, and trans* (LGBTQ+) community are also underrepresented in STEM. The potentially invisible nature of these identities can make their experiences difficult to study. With this in mind, we developed a survey to measure there presentation of LGBTQ+ students in a general chemistry classroom and ask about their sense of belonging in the classroom. Here, we report on effective ways to ask students to self-report their gender and sexual orientation identities and the census data of the survey. In the general chemistry course surveyed, 10.7% of students identified as having a minority sexual orientation (LGBQA) and 1.7% of the students identified as having a nonbinary gender (trans*/nonbinary). We also find that these identities can be fluid and change over time scales as short as a single semester. These results provide evidence that these LGBTQ+ students are not underrepresented in introductory science courses and that losses of these students from the STEM career pipeline likely occur later during their time in college. In order to increase the retention of these students in STEM fields, their experiences in the classroom should be further explored and considered when developing curricula.