The National Science Foundation's Survey of Earned Doctorates is the best place to understand the demographics of chemistry PhD holders. The latest data is from 2018.
For the 1711 chemistry PhD recipients in 2018 who were US citizens or permanent residents, 77 (4.5%) were Black. https://ncses.nsf.gov/pubs/nsf20301/data-tables/?tableCtr1746
For the 240 analytical chemistry PhD recipients in 2018 who were US citizens or permanent residents, 12 (5.0%) were Black.
For the 113 chemical biology PhD recipients in 2018 who were US citizens or permanent residents, 2 (1.8%) were Black.
For the 253 inorganic chemistry PhD recipients in 2018 who were US citizens or permanent residents, 10 (4.0%) were Black.
For the 52 medicinal chemistry PhD recipients in 2018 who were US citizens or permanent residents, 5 (9.6%) were Black.
For the 371 organic chemistry PhD recipients in 2018 who were US citizens or permanent residents, 23 (6.2%) were Black.
For the 239 physical chemistry PhD recipients in 2018 who were US citizens or permanent residents, 7 (2.9%) were Black.
For the 63 polymer chemistry PhD recipients in 2018 who were US citizens or permanent residents, 1 (1.6%) were Black.
For the 64 theoretical chemistry PhD recipients in 2018 who were US citizens or permanent residents, 3 (4.7%) were Black.
For the 204 general chemistry PhD recipients in 2018 who were US citizens or permanent residents, 10 (4.9%) were Black.
For the 112 "chemistry, other" PhD recipients in 2018 who were US citizens or permanent residents, 4 (3.6%) were Black.
The deeply disturbing aspect of this thread is that these 2018 PhDs will be the faculty candidates of 2020 or 2021, and thus the assistant professors of 2022 and 2023.
This inequality is already baked into the cake.