Smoke Bomb

Physical sciences 416/436. CHEMICAL REACTION

The proposed procedure must be strictly followed.

KNO3 when heated releases oxygen and becomes KNO2. It is the oxygen that causes rapid combustion of the sugar. This works for a range of other combustible materials. Mix KNO3 in, and they burn much more quickly, even explosively. This is the basis of old fashioned gunpowder. I believe that originally KNO3 was extracted from under manure piles. Not a pleasant task! 9.6 KNO3 + C12H22O11 --> 4.8 K2CO3 + 7.2 CO2 + 11 H2O + 4.8 N2 (approx.) So, 970g KNO3 and 342g sucrose, which is 74% KNO3 and 26% sucrose. This produces 662g of potassium carbonate. And, as you know, in a well made (ie, intimately mixed) LE of this type there is little slag or "pearling" left after combustion. Meaning that all 662g of potassium carbonate is dispersed as smoke (well, and droplets flung about, but largely as smoke). In other words, 50% of the mass of the charge ends up as smoke. Increasing the amount of fuel decreases the %age of KNO3, therefore decreasing the amount of K2CO3 that can be made, reducing the max possible amount of smoke. Also, burning will be less vigorous, so it will be less well dispersed. I think the idea to use sub-optimal amounts of oxidiser came from the common belief that "incomplete combustion produces smoke", which is not always the case...

Saltpeter Potassium nitrate (KNO3) also known as saltpeter and in the 1800’s as, nitrate of potassa, or saltpetr. It has many uses including the manufacture of gunpowder, gun cotton, dynamite fusses and it is a good oxidizer. It can be extracted from green plants, ashes, and almost any dirt except sand and on the large scale from cow manure. Before the 1900’s people in Sweden had to pay their land taxis in saltpeter; we will be using the same method of extraction that they used.

Step 1: Make a heap Gather a large amount of cow manure or you can use some planting soil. Now mix the cow manure with some green plant life, dirt and a little bit of ash from burned thistles, worm wood, ash from tree bark or normal wood ashes, The ashes contain potassium carbonate which helps extract the minerals in the pile. The pile is also known as a saltpeter bed. If you can you should mix in some potato leaves so that the dirt and cow manure just cover the leaves; potato leaves are good because they contain a lot of potassium. The pile should be about ½ cow manure and it should be 6 to 7 feat tall so that most of it is exposed to the atmosphere and if you have some straw mix that in too it will help circulate the pile. Your pile should be setting on something that is waterproof so that the (KNO3) doesn’t seep into the

ground, a peace of plie wood or a layer of clay will work. Now you need a roof over it; you can use a tarp and some cinderblocks. It should look like this. If you don’t have enough cinderblocks you could attach one side of the tarp to a fixed structure like a shed.

Step 2: Pore stale cow urine over the mound Lant (stale urine) is pored over the pile at least once a week for three or fore months or until thin light yellowish crystals collect on the surface. Stop poring lant over the pile and wait until you see a layer of potassium nitrate efflorescing over the surface 6 to 10 centimeters in thickness. The trick hear is knowing what to look for, potassium nitrate collects in light yellowish crystals. This takes longer in dry climates like Arizona. Next scrape off the top layer and start purifying it, later when you see more crystals you will scrape off the next layer and so on until the pile needs replaced.

Step 3: Treatment of the ripe saltpeter earth