Dear Imdad Ullah Qureshi , ppm is the ratio of your compound (acetone) to the whole mixture. Usually the mixture can be a two components one, where your compound is mixed with a solvent or matrix.
In liquid solutions 10ppm means 10uL (microliters) of acetone by liter of solution (imagine that the other component, is just water, you will pipete 10uL of acetone and place them into a volumetric flask of 1L, then add water till the mark.
Because your 10ppm acetone solution is for gas sensing, we cannot know if your solvent is water or air (or other gas), but the idea is the same for a final volume/mass/quantity of 1million (grams, liters, molecules),10 must be of acetone.
Hope it helps.
Dear Imadaullah
If you want to prepare 10 ppm v/v acetone in water, then the answer given by Manual Gomez is correct.
You have to bear in mind that acetone is a volatile solvent!!
Imdad Ullah Qureshi
While I do not disagree with the answers provided above, then are a few caveats that are hinted at above, but the practical implications are not explicitly stated.
The comment '(imagine that the other component, is just water, you will pipete 10uL of acetone and place them into a volumetric flask of 1L, then add water till the mark' is theoretically correct (other than the misspelling of pipette). However, as stated in the second answer above 'You have to bear in mind that acetone is a volatile solvent!!' (Note only one exclamation point is needed. It is not English language with 2...). Thus it will be found difficult to pipette such a small quantity of material. Plus it would not be added directly into a 1 L volumetric flask - it would evaporate before it even reached the bottom. The 1 L flask (if this is the route) would already be filled almost to the top and the acetone added to this to reduce the chances of evaporation (probably submerging the tip under the water and flushing out). The flask would then be made up to the mark with more water. This route is normal as, in many situations, volume changes occur (for example if heat is evolved in dissolution) and these must be allowed to dissipate before the final solution is made up.
Given the volatility of acetone, my preferred routing would be different. I'd make up an approximate 1000 ppm stock solution of acetone in diluent (e.g. water) and calculate the exact amount by appropriate means (titration, spectroscopy etc). I'd then dilute a portion of this solution down approximately 100-fold to make the 10 ppm solution. Given that exactly 10 ppm isn't probably going to be necessary, in reality, I'd make up the 1000 ppm solution, dilute 100-fold, and then measure the actual concentration by appropriate means (e.g. 9.7 ppm probably wouldn't be a problem - it's just needed to be known).
Finally one must be careful with the term '10 ppm'. The answers above imply that this is volume/volume (v/v). In many situations (e.g. water industry) ppm is weight/volume (w/v). As the density of acetone is not 1 g/cm3 then there is a big difference between v/v and w/v. 10 ppm could also be a molar quantity...
Last, but not least. 10 μL of water is about 1/5 (one fifth) of a drop (one drop of water is normally equated to 0.05 mL)! So, again, the practical difficulties of handling small quantities of a volatile liquid can be seen... And in gas/vapor, it's another ball game...
Please read the paper given below. here I have used simple equation for preparing gas concentration ppm, hope this will solve your problem.
doi.org/10.1007/s10854-020-04760-2
I agree with Prof.Rawle. If you don't check the concentration of acetone in the final prepared solution,you can not be sure that you have the required solution.The usual way of preparing dilute solution from more concentrated one was also mentioned.
Pukhrambam Dipak
The article is $39.95. I assume it can be requested from you?
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