DILUTIONS AND STANDARDS

What is the concentration in mg/dL of protein in the 6th tube of a 1:2 serial dilution of the serum? 12. 5 mL of a stock urea nitrogen standard contains 1mg Nitrogen. 5 mL is diluted to 10 mLs. 1 mL of this is rediluted to 10mL. 2.5 mL of this is rediluted to 25 mL. What is the concentration of nitrogen per mL of the final dilution. 13. ................
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