?hydrometer analysis

[dirtdrpa]

im using an 152H scale. my distilled water only level is reading at 0, but my sodium hexametaphosphate mix is reading at 40. my mixture is 40 grams per liter as told. if anyone can help, much appreciated. cant seem to find what the mixture should read at. the high 40 reading is leading me to be unable to read my actual hydrometer test. i.e. its off the scale high.

 

[iandig]

I think you may have misread, mis-understood the standard. I will need to check with our lab, but the reference cylinder with the Sodium Hex in it should not be all at 40 g/l, from memory you mix the sodium hex at 40 g/l and add 50ml to the soil sample to floculate the particles, then in turn you add 50ml of the same sodium hex to a litre of the distilled water in the reference cylinder. This way you have around the same dilution in the cylinder as you would do with the soil and water. Typically this will give a reading of 0.5, i.e. you add/subtract this from the hydro reading of the soil to 'correct; it for the affect of the sodium hex.

 

[dirtdrpa]

mixture for sodium hex is 40g/l. mixed approx 150 grams for a galloon. 1 gallon = 3.76 liters. 3.76 liters x 40 grams = 150 grams. am i wrong? using a 50 gram sample. steps done properly but still getting a reading over 60. never happened to me before. still trying to figure it out.

 

[Stoph]

Your mixture sounds correct. But I think what IANDIG was referring to is the fact that you only use 50 mL of the 40 g/L sodium hex mixture per cylinder. The rest is either deionzied or distilled water.

 

[dirtdrpa]

thanks, i realized that i accidentally added sod hex to the full 1000ml, instead of distilled water. oops.