Your package chemtool failed to build from source in current rawhide. https://koji.fedoraproject.org/koji/taskinfo?taskID=17710710 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_26_Mass_Rebuild
Created attachment 1251512 [details] build.log
Created attachment 1251513 [details] root.log
Created attachment 1251514 [details] state.log
Desktop file doesn't validate, should be easy to fix. Proven packagers are welcome to do it.
Fixed in rawhide.