In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The patient ' s subjective assessment of mood rating , an objective test of performance , a test for amnesia , and vital signs were recorded for up to 300 min after administration of the trial drug .
### Output Text:
The patient ' s subjective assessment of mood rating , an objective test of performance , a test for amnesia , and vital signs were recorded for up to 300 min after administration of the trial drug . 