I'm trying to see the relationship between changing sample sizes for water testing.
Red is the instructed sample size.
FAS-DPD Chlorine Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ...................................... Precision
------------------------------------------------------------------------------------------------------------
2.5 mL ............... 2 .......... 1/4 heaping scoop R-0870 - 2 drops R-0003 for CC's ......... +/- one drop (2 ppm) up to 10 drops or 10% after 10 drops
5 mL .................. 1 .......... 1/2 heaping scoop R-0870 - 3 drops R-0003 for CC's ......... +/- one drop (1 ppm) up to 10 drops or 10% after 10 drops
10 mL ............... 0.5 ......... 1 heaping scoop R-0870 - 5 drops R-0003 for CC's ............ +/- one drop (0.5 ppm) up to 10 drops or 10% after 10 drops
15 mL ............... 0.33 ........ 1.5 heaping scoops R-0870 - 8 drops R-0003 for CC's ....... +/- one drop (0.3 ppm) up to 10 drops or 10% after 10 drops
20 mL ............... 0.25 ........ 2.0 heaping scoops R-0870 - 10 drops R-0003 for CC's ...... +/- one drop (0.25 ppm) up to 10 drops or 10% after 10 drops
25 mL ............... 0.2 .......... 2.5 heaping scoops R-0870 - 13 drops R-0003 for CC's ...... +/- one drop (0.2) up to 10 drops or 10% after 10 drops
TA Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ............ Precision
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10 mL .................. 25 ............... 1 drop R-0007, 2 drops R-0008 ........ +/- one drop (25 ppm) up to 10 drops or 10% after 10 drops
15 mL .................. 16.66 ........... 1 drop R-0007, 3 drops R-0008 ........ +/- one drop (16.6 ppm) up to 10 drops or 10% after 10 drops
20 mL .................. 12.5 ............ 2 drops R-0007, 4 drops R-0008 ....... +/- one drop (12.5 ppm) up to 10 drops or 10% after 10 drops
25 mL .................. 10 ............... 2 drops R-0007, 5 drops R-0008........ +/- one drop (10 ppm) up to 10 drops or 10% after 10 drops
CH Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ........... Precision
-----------------------------------------------------------------------------
5 mL ................. 50 ................ 5 drops R-0010, 2 drops R-0011L ...... +/- one drop (50 ppm) up to 10 drops or 10% after 10 drops
10 mL ............... 25 ................ 10 drops R-0010, 3 drops R-0011L ..... +/- one drop (25 ppm) up to 10 drops or 10% after 10 drops
15 mL ............... 16.66 ........... 15 drops R-0010, 5 drops R-0011L ...... +/- one drop (16.6 ppm) up to 10 drops or 10% after 10 drops
20 mL ............... 12.5 ............. 20 drops R-0010, 6 drops R-0011L ...... +/- one drop (12.5 ppm) up to 10 drops or 10% after 10 drops
25 mL ............... 10 ................ 25 drops R-0010, 8 drops R-0011L ..... +/- one drop (10 ppm) up to 10 drops or 10% after 10 drops
My math for the second column seems to be correct but the other reagent amounts don't seem to be right because the CH extended test kit directions says for a 25 mL size to use 20 drops R-0010 and 5 drops R-0011L.
If you double the sample size wouldn't you have to double the amount of other reagents? 25mL is 2.5 times 10 mL so multiply 10 mLs drops by 2.5 and round up as needed?
Also I assume the precision would still be "+/- one drop up to 10 drops or 10% after" when changing sample sizes or would it?
Red is the instructed sample size.
FAS-DPD Chlorine Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ...................................... Precision
------------------------------------------------------------------------------------------------------------
2.5 mL ............... 2 .......... 1/4 heaping scoop R-0870 - 2 drops R-0003 for CC's ......... +/- one drop (2 ppm) up to 10 drops or 10% after 10 drops
5 mL .................. 1 .......... 1/2 heaping scoop R-0870 - 3 drops R-0003 for CC's ......... +/- one drop (1 ppm) up to 10 drops or 10% after 10 drops
10 mL ............... 0.5 ......... 1 heaping scoop R-0870 - 5 drops R-0003 for CC's ............ +/- one drop (0.5 ppm) up to 10 drops or 10% after 10 drops
15 mL ............... 0.33 ........ 1.5 heaping scoops R-0870 - 8 drops R-0003 for CC's ....... +/- one drop (0.3 ppm) up to 10 drops or 10% after 10 drops
20 mL ............... 0.25 ........ 2.0 heaping scoops R-0870 - 10 drops R-0003 for CC's ...... +/- one drop (0.25 ppm) up to 10 drops or 10% after 10 drops
25 mL ............... 0.2 .......... 2.5 heaping scoops R-0870 - 13 drops R-0003 for CC's ...... +/- one drop (0.2) up to 10 drops or 10% after 10 drops
TA Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ............ Precision
-----------------------------------------------------------------------------
10 mL .................. 25 ............... 1 drop R-0007, 2 drops R-0008 ........ +/- one drop (25 ppm) up to 10 drops or 10% after 10 drops
15 mL .................. 16.66 ........... 1 drop R-0007, 3 drops R-0008 ........ +/- one drop (16.6 ppm) up to 10 drops or 10% after 10 drops
20 mL .................. 12.5 ............ 2 drops R-0007, 4 drops R-0008 ....... +/- one drop (12.5 ppm) up to 10 drops or 10% after 10 drops
25 mL .................. 10 ............... 2 drops R-0007, 5 drops R-0008........ +/- one drop (10 ppm) up to 10 drops or 10% after 10 drops
CH Test
Sample Size... 1 Drop = ? ppm ..... Other Reagent Drops Amount ........... Precision
-----------------------------------------------------------------------------
5 mL ................. 50 ................ 5 drops R-0010, 2 drops R-0011L ...... +/- one drop (50 ppm) up to 10 drops or 10% after 10 drops
10 mL ............... 25 ................ 10 drops R-0010, 3 drops R-0011L ..... +/- one drop (25 ppm) up to 10 drops or 10% after 10 drops
15 mL ............... 16.66 ........... 15 drops R-0010, 5 drops R-0011L ...... +/- one drop (16.6 ppm) up to 10 drops or 10% after 10 drops
20 mL ............... 12.5 ............. 20 drops R-0010, 6 drops R-0011L ...... +/- one drop (12.5 ppm) up to 10 drops or 10% after 10 drops
25 mL ............... 10 ................ 25 drops R-0010, 8 drops R-0011L ..... +/- one drop (10 ppm) up to 10 drops or 10% after 10 drops
My math for the second column seems to be correct but the other reagent amounts don't seem to be right because the CH extended test kit directions says for a 25 mL size to use 20 drops R-0010 and 5 drops R-0011L.
If you double the sample size wouldn't you have to double the amount of other reagents? 25mL is 2.5 times 10 mL so multiply 10 mLs drops by 2.5 and round up as needed?
Also I assume the precision would still be "+/- one drop up to 10 drops or 10% after" when changing sample sizes or would it?
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