Lightweight Peat's Mucky Muck soil testing

[acespicoli]

Do you want to get into valence and electrons?

 

[acespicoli]

Forget till depth pounds per acre shit.

Work in liters and covert to gallons at the end. Easy

Thing with this stuff is, at least for me, complicated until you do a couple of your own soil prescriptions and it will be super simple.

It's a learn by doing. It's way easier than it sounds or reads.

agreed

 

[biggreg]

Do you want to get into valence and electrons?

Not really

But you should study up on miliequilivants of the base cations , atomic weights and valences if you want.

Come back with the answer to this:

if a soil has a CEC of 25 meq/100g, how many mg/kg of pure elemental Ca would saturate the exchange capacity 100%

 

[acespicoli]

kilo=1000g
25meq/100g

25*10?
250

 

[acespicoli]

The meq wt of Ca2+ is 20 mg/meq

 

[acespicoli]

20 25 250?
125g what did you come up with?

 

[biggreg]

Keep working on it, you're warm

 

[acespicoli]

Thats some high cec soil bro...

 

[biggreg]

Looking for mg/kg of Ca

 

[acespicoli]

20*25*10
5000

 

[biggreg]

Thats some high cec soil bro...

High CEC per volume, yes.

High CEC per mass, if it's 1g/1cm3 bulk density soil? YES! ( same exchange capacity per mass as per volume)


High CEC per mass, meq/100g in a .3g/cm3 lightweight soil? NO!

25meq/100g x .3g/cm3 = 7.5 meq/100cm3 a pretty low CEC soil. Just on the low end of acceptable if you want some buffer for your bottle fed plants.

The CEC reported on all of our under measured scooped tests are not the correct CEC.
My scooped soil report said about 20 meq/100g but the direct measure CEC test and the correct weigh in test said 40meq/100g

The difference in the ratio of actual CEC vs your "Scooped" CEC will vary with all our various densities.

 

[acespicoli]

Calcium
Chemical Element
Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray Group 2 alkaline earth metal, fifth-most-abundant element by mass in the Earth's crust. Wikipedia
Symbol: Ca
Atomic number: 20
Atomic mass: 40.078 u ± 0.004 u
Electron configuration: [Ar] 4s2
Discovered: 1808
Melting point: 1,548°F (842°C)
Discoverer: Humphry Davy


Atomic mass: 40.078 u ± 0.004 u 40/2=20

What is the valence of Ca and what is its milliequivalent weight if the atomic weight is 40?

Calcium often occurs as a divalent, positively charged cation (Ca2+). It appears in Group II of a Periodic Table and readily looses two electrons from its outer orbital, giving it a divalent (2) valence. The meq wt can be determined by dividing the atomic weight by the valence

also we can take that to ppm ?

 

[biggreg]

And the mis-measurement of mass on our soil samples, the resultant skewed low values of the CEC and elemental ppm, and the realization of what was screwing up the test, brings me back to my self-indulgent venting of my frustration via meme:

 

[biggreg]

 

[acespicoli]

Precision refers to the closeness of two or more measurements to each other. Using the example above, if you weigh a given substance five times, and get 3.2 kg each time, then your measurement is very precise. Precision is independent of accuracy. You can be very precise but inaccurate, as described above.

 

[biggreg]

also we can take that to ppm ?

The answer is in ppm.

1 million mg in a kg

A CEC of 25meq/100g

How many mg/kg Ca to 100% saturate the CEC?

Hint: be mindful of the units.

 

[acespicoli]

ppm 1/1,000,000

 

[biggreg]

Pasted stuff

It's beneficial to us all if we focus our conversation and work the topic at hand.

 

[acespicoli]

500ppm?

 

[biggreg]

Come back with the answer. You can do it ace