The Vespiary

The Hive => Newbee Forum => Topic started by: grellobanans on May 16, 2003, 02:25:00 AM

Title: MeNO2 Percent Discrepancy
Post by: grellobanans on May 16, 2003, 02:25:00 AM
Used TFSE. Found 2 different equations for calculating nitro %, forgot the post #'s, so:
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Once you've got the density, use the formula (which assumes ideal solution behaviour, but oh well):

(2.889*d -2.285)*100
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There's also:

EDIT: I plotted some points and did regression on it... the formula for w/w is:
x = -3.0173*(SG)^2 + 8.6901*SG - 4.9828
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Swim got ~19% for the first equation, and ~25% for the second. Which equation is more accurate? The second one was determined experimentally, the first assumes ideal behavior. If there is no answer, swim will probably go with the lower value since a bit of excess shouldn't hurt. Swim is anal about these things.
Title: What's your SG?
Post by: Chromic on May 16, 2003, 07:04:00 PM
What's your SG? I assume it's ~0.856g/ml.

This means that your nitromethane, assuming the only dilutent is methanol, is about 19% (v/v) or 25% (w/w).

This means in 100ml there is 19ml nitromethane and in 100g there is 25g nitromethane.

Do the math if you wish, it'll all work out. The data about methanol/nitromethane is:

Density   w/w
0.791   0%
0.8   3.70%
0.81   7.71%
0.8125   8.69%
0.82   11.62%
0.9   39.79%
1   68.67%
1.1   92.29%
1.137   100%

methanol 0.791g/ml
nitromethane 1.137g/ml

With that you should be able to double check all the #s.
Title: do the math or wash it with water and get 100%
Post by: Antibody2 on May 16, 2003, 08:28:00 PM
do the math  or wash it with water and get 100% nitromethane

for what its worth the last gallon of RC fuel swim saw was labeled 60%Nitro, but it ended up being closer to 30%.
Title: No!
Post by: Chromic on May 16, 2003, 10:43:00 PM
>or wash it with water and get 100% nitromethane

Ab2, no!!! NM is soluble in water and vice-versa. You'll get a layer with methanol, water and nitromethane, and another with nitromethane, methanol and water! Don't wash with water. Follow directions--especially if you're anal, because I am too.  :P