A 0.1070 g rock sample containing an unknown amount of Ca was dissolved in HCl and...

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A 0.1070 g rock sample containing an unknown amount of Ca was dissolved in HCl and diluted to 100.0 mL. Aliquots of 20.00 mL from this solution were added to different volumes of a 2.08 ug/mL Ca standard solution and diluted to 200.0 mL. The emission intensity of these solutions was measured using atomic emission spectroscopy. The results are shown in the table. Unknown volume (mL) Standard volume (mL) Final volume (mL) Emission Intensity 20.00 0.00 200.0 211.0 20.00 5.00 200.0 397.0 20.00 10.00 200.0 621.0 20.00 15.00 200.0 815.0 20.00 20.00 200.0 1005.0 Find the weight percent of Ca in the rock sample and its uncertainty using the method of standard additions. weight percent: 0.05169 % Ca 0.0007 % Incorrect A 0.1070 g rock sample containing an unknown amount of Ca was dissolved in HCl and diluted to 100.0 mL. Aliquots of 20.00 mL from this solution were added to different volumes of a 2.08 ug/mL Ca standard solution and diluted to 200.0 mL. The emission intensity of these solutions was measured using atomic emission spectroscopy. The results are shown in the table. Unknown volume (mL) Standard volume (mL) Final volume (mL) Emission Intensity 20.00 0.00 200.0 211.0 20.00 5.00 200.0 397.0 20.00 10.00 200.0 621.0 20.00 15.00 200.0 815.0 20.00 20.00 200.0 1005.0 Find the weight percent of Ca in the rock sample and its uncertainty using the method of standard additions. weight percent: 0.05169 % Ca 0.0007 % Incorrect