43. Solution to Chemistry Problem

3. To determine the sodium content in the wastewater of soda production, the flame photometry method was used. Direct determination is carried out when the sodium content in the sample is from 0.1 to 10 mg/l. More concentrated waters are pre-diluted, and less concentrated ones are evaporated. The volume of the initial sample is 500 ml, after evaporation - indicated in Table 2. The determination was carried out using the calibration graph method. The data for its construction are given in Table 1. Calculate the sodium content (mg/l) in the wastewater under study. Table 1
Results of photometry of standard NaCl solutions
Sodium concentration, mg/dm3 1.0 2.0 3.0 4.0 5.0 7.0 10.0
Relative radiation intensity (Irel.) 30.0 36.0 40.0 44.0 48.0 56.0 70.0

Characteristics of the studied solutions
Parameters Options and initial data

3
Sample volume after evaporation, ml 100
Relative radiation intensity (Irel.) 44