AMMONIUM NITRATE, a salt of ammonia and nitric acid, is a colourless, crystalline substance melting at 169 C. It is highly soluble in water and soluble in alcohol and liquid ammonia. Heating may cause violent combustion or explosion.
The British thermal unit (BTU or Btu) is a traditional unit of work equal to about 1055 joules. It is the amount of work needed to raise the temperature of one pound of water by one degree Fahrenheit (Physical analogue: one four-inch wooden kitchen match consumed completely generates approximately 1 BTU).In science, the joule, the SI unit of energy, has largely replaced the BTU.efinitions of the BTU based on different water temperatures can therefore vary by up to 0.5%. A BTU can be approximated as the heat produced by burning a single wooden kitchen match or as the amount of energy it takes to lift a one-pound weight 778 feet (237 m).
Btu-also called British thermal unit is the amount of energy required to raise the temperature of one pound of water one degree Fahrenheit. Watt (W/m2 or Wm-2) - a metric unit of measurement of the intensity of radiation in watts over a square meter surface. One watt is equal to one joule of work per second. A kilowatt (kW) is the same as 1000 watts. In the previous section, we developed the concept of energy. We now must be able to measure and quantify it, using a standard set of units. Worldwide, two systems of units of measurement are commoly used today: the Metric System (Systeme International) and the British System. The units of energy described in these systems are derived from a technical definition of energy used by physicists.