Serum taken from a patient being treated with lithium for
manic-depressive illness was analyzed for lithium concentration. a
reading of 212 units was obtained for the intensity of the 671 nm
red emission line. then 1.00 ml of a 11.2 mm lithium standard was
added to 9.00 ml of serum, and this spiked serum gave an intensity
reading of 546 units. what is the original concentration of li in
the serum?