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The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.

In a chemical reaction, the final amount of the products is determined by the a. universal gas law b. law of definite proportions c. air pressure d. temperature e. none of the above me

Each step in the following process has a yield of 70% ch4 + 4cl2 yield ccl4 +4hcl ccl4 + 2hf yield ccl2f2 + 2hcl of 4.50 mole ch4 reacts what is the total amount of hcl produced