Aspirin Spray

[Ray]

In that study, they used a 15 millimole concentration. That sounded slim to me when I initially thought about it, but my numbers flip in the opposite way:

A mole of acetylsalicylic acid is 180.16g, a mole of water is 18.01 grams. Therefore, you need to dissolve 15/1000 x 180.16 = 2.7 grams of acetylsalicylic acid in 18.01 grams of water to make that concentration.

As a typical aspiring is 500 mg (1/2 gram), and a quart of water is roughly 950 g, you would need to dissolve 285 aspirin in a quart of water to achieve that concentration.

I ain't puttin' that on MY plants!

[newflasker]

Originally Posted by Ray

In that study, they used a 15 millimole concentration. That sounded slim to me when I initially thought about it, but my numbers flip in the opposite way:

A mole of acetylsalicylic acid is 180.16g, a mole of water is 18.01 grams. Therefore, you need to dissolve 15/1000 x 180.16 = 2.7 grams of acetylsalicylic acid in 18.01 grams of water to make that concentration.

As a typical aspiring is 500 mg (1/2 gram), and a quart of water is roughly 950 g, you would need to dissolve 285 aspirin in a quart of water to achieve that concentration.

I ain't puttin' that on MY plants!

"dissolve 285 aspirin in a quart of water" ???. It's nonsense!!!! I agree that we ain't puttin' that on our plants! but NOT agree with the calculation!!!! In scientific concentration definition, 15 millimole concentration means 15 millimole in a LITTER of water NOT in a mole of water!!!. So using 1.5 tablets of Aspirin (81 mg) in 2 gallons of water (in the article) made sense. That is the way we used to put few aspirin tables in flower pots to keep cutting flower fresh longer.

[camille1585]

Originally Posted by newflasker

"dissolve 285 aspirin in a quart of water" ???. It's nonsense!!!! I agree that we ain't puttin' that on our plants! but NOT agree with the calculation!!!! In scientific concentration definition, 15 millimole concentration means 15 millimole in a LITTER of water NOT in a mole of water!!!. So using 1.5 tablets of Aspirin (81 mg) in 2 gallons of water (in the article) made sense. That is the way we used to put few aspirin tables in flower pots to keep cutting flower fresh longer.

I though there was something wrong with the calculation! Your answer seems much more reasonable. I never was any good at calculating this sort of stuff, in gives me a head ache. So how did you calculate the 81mg for 2 gallons?

[M68]

Originally Posted by newflasker

"dissolve 285 aspirin in a quart of water" ???. It's nonsense!!!! I agree that we ain't puttin' that on our plants! but NOT agree with the calculation!!!! In scientific concentration definition, 15 millimole concentration means 15 millimole in a LITTER of water NOT in a mole of water!!!. So using 1.5 tablets of Aspirin (81 mg) in 2 gallons of water (in the article) made sense. That is the way we used to put few aspirin tables in flower pots to keep cutting flower fresh longer.

15 mmol/l=.015mol/l=2.7 g/l
If its a 500 mg pill, that would be 5.4 tablets per liter, which would be about 20 tablets per gallon. That's not 285, but it's also not 1.5 tablets in 2 gallons

[newflasker]

Originally Posted by M68

15 mmol/l=.015mol/l=2.7 g/l
If its a 500 mg pill, that would be 5.4 tablets per liter, which would be about 20 tablets per gallon. That's not 285, but it's also not 1.5 tablets in 2 gallons

In the study, 15 mili-mole concentration is used to figure out how much salicylic acid can be absorbed by plant and find out that "However, little of the salicylic acid (1.4%) moved into new plant tissues" So MARTHA MCBURNEY, the master gardener uses 1.5 tablets (81 mg) in 2 gallons. Retry your calculation you will understand why Martha uses 1.5 tablets. Remember that this is the pratical dosage Martha uses with her experience and it's not necessary exactly the same number with your calculation. Cheers.

[M68]

Originally Posted by newflasker

In the study, 15 mili-mole concentration is used to figure out how much salicylic acid can be absorbed by plant and find out that "However, little of the salicylic acid (1.4%) moved into new plant tissues" So MARTHA MCBURNEY, the master gardener uses 1.5 tablets (81 mg) in 2 gallons. Retry your calculation you will understand why Martha uses 1.5 tablets. Remember that this is the pratical dosage Martha uses with her experience and it's not necessary exactly the same number with your calculation. Cheers.

That would be .09 mM. Whats your point?

[Sun rm.N.E.]

Please note the above quote is different from what I read

"The dosage Martha arrived at after numerous experiments was 1.5 aspirin (81 gr. strength) to two gallons of water. Important note: The tablets should be the uncoated type. She also added two tablespoons of yucca extract to help the aspirin water stick better to the leaves. (The yucca extract can be substituted with a mild liquid soap)"

81gr. is not in miligrams, probably 81 grains (the pharmacy unit).
1 grain = 60mg.