Multiple Standard Additions

This video goes through the planning and calculations of both variable volume and constant volume multiple standard additions approaches.

[@amornratrat]

Thank you for explaining

[@mysarababekir569]

Thank you very much for golden information

[@mell9508]

Robyn. Great videos I'm so grateful to have landed on them. Any chance you have any references for regarding multiple standard additions, with variable volume?

[@user-rq6dx5ro3w]

nice explanation, very helpful, but what if the unknown matrix signal is negative, suppose -0.345 AU?

[@mahditabatabaee5880]

Many thanks

[@ananyamohanty7088]

Thank you for the great video. While we are taking the dilution into account, won't we also consider the reduction in sample volume caused due to signal measurement? The V0 becomes a variable then..?

[@robyngoacher8521]

Your question relates to whether "variable volume" or "constant volume" standard additions are done. In variable volume standard additions, the exact same solution is measured, spiked with standard, measured again, spiked with more standard and measured again (and so on). In that kind of standard addition, you cannot use a measurement technique that consumes sample. If you will consume the sample during measurement (even if that means losses due to transferring into and out of a cuvette for spectroscopy), then you should use constant volume standard additions. In constant volume standard additions, the V0 is the same for all flasks and you are able to do the math without needing to account for change in V0. So, no, the V0 does not become a variable. I hope that helps.