14822
Zr ( IV ) increased Hb binding constant to alpha - ZrP by 43 - fold , and affinity enhancements followed the trend Zr ( IV ) > H ( I ) > Mg ( II ) > Na ( I ) > Ca ( II ) > Cr ( III ) .
 Zr ( IV ), alpha - ZrP, Zr ( IV ), H ( I ), Mg ( II ), Na ( I ), Ca ( II ), Cr ( III )
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Zr ( IV ), alpha - ZrP, Zr ( IV ), H ( I ), Mg ( II ), Na ( I ), Ca ( II ), Cr ( III )