[dnbwise]

I added 10 mL of toothpaste into a beaker and used a F- detecting electrode to take measurments of potential (mV). I used standards to construct a calibration curve and calculated [F-] of toothpaste by the calibration curve. I have the fluoride concentration in ppm ([F-] = 1.919 ppm) now I need to find grams F-. (1ppm = 1ug/mL)

(1.919 ug/mL)(10^-6g/ug)(10ml) = 1.919*10^-5 g

does this look like the correct calculation for determining F- grams from the [F-]?

[sdekivit]

looks correct.

[skyaintsnow]

it's right.

An easier way to convert the unit is to use the equivalent unit of ppm, mg/liter. You don't need to worry about the 10⁶ part then.