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: Fifteen min later , animals received CaCl2 , NaHCO3 , or saline .
### Output Text:
Fifteen min later , animals received <span class="chemical">CaCl2</span> , <span class="chemical">NaHCO3</span> , or saline . 