Light blue gas

Ozone (O3) is a light blue gas (boiling point =—110°C). It has a unique electric odor and is highly reactive. Its structure is three oxygen atoms linked together in the... 

Liquid ozone below its boiling point (- 111.3°C). Ozone is a toxic, light-blue gas with a pungent odor. 

Ozone is a rather toxic, light-blue gas (b.p. 111.3°C). Its pungent odor is noticeable around... 

The liquid becomes progressively darker in colour, and then effervesces gently as ethylene is evolved. Allow the gas to escape from the delivery-tube in T for several minutes in order to sweep out the air in F and B. Now fill a test-tube with water, close it with the finger, and invert the tube in the water in T over the delivery-tube so that a sample of the gas collects in the tube. Close the tube again with the finger, and then light the gas at a Bunsen burner at a safe distance from the apparatus. If the tube contains pure ethylene, the latter burns with a clear pale blue (almost invisible) flame if the ethylene still contains air, the mixture in the test-tube ignites with a sharp report. Allow the... 

Blue gas, or blue-water gas, so-called because of the color of the flame upon burning (10), was discovered in 1780 when steam was passed over incandescent carbon (qv), and the blue-water gas process was developed over the period 1859—1875. Successfiil commercial appHcation of the process came about in 1875 with the introduction of the carburetted gas jet. The heating value of the gas was low, ca 10.2 MJ /m (275 Btu/fT), and on occasion oil was added to the gas to enhance the heating value. The new product was given the name carburetted water gas and the technique satisfied part of the original aim by adding luminosity to gas lights (10). 

Observable Characteristics - Physical State (as shipped) Liquefies gas Color. Light blue Odor None. 

When the flame is lit, adjust the gas flow and oxygen flow so that the flame is blue with an inner light-blue cone. A yellow flame is too cool and needs more oxygen. Your teacher may have additional directions on the operation of the Bunsen burner. 

Heat a little dry basic copper carbonate by shaking it in a test tube at some distance above a small flame. The light blue powder is quickly changed to black, and the seething of the dry powder shows that a gas is being expelled. A drop of lime water is clouded by the gas. To the residue after it has cooled add 5 cc. of water and then a little HC1 and note that the black powder dissolves without effervescence. 

Acetylene is by far the most important commercial alkyne. Acetylene is an important industrial feedstock, but its largest use is as the fuel for the oxyacetylene welding torch. Acetylene is a colorless, foul-smelling gas that burns in air with a yellow, sooty flame. When the flame is supplied with pure oxygen, however, the color turns to light blue, and the flame temperature increases dramatically. A comparison of the heat of combustion for acetylene with those of ethene and ethane shows why this gas makes an excellent fuel for a high-temperature flame. 

When ammonia gas was introduced into an argon plasma jet at a flow rate of 60 seem, all argon emission lines disappeared, and a very short but brilliant light-blue flame was formed. A very strong NH emission band was observed. In the ammonia radio frequency plasma, some very weak N2 emission bands due to N2 second positive appeared, but in the ammonia flame formed in an argon plasma jet no emission related to N2 species was observed. 

To avoid an excess of ozone, the gas is metered by using conventional flow meters. Otherwise, the introduction of ozone is maintained until ozone appears in the exit gas. The presence of ozone is easily recognized by the starch-iodine reaction. The exit gas is passed through an aqueous solution containing 5% of alkaline iodide, 5% of sulfuric acid, and a few drops of a starch solution. Iodine, which is liberated by ozone, forms a dark blue color with starch [7i], Another sign of the end of ozonization is the light-blue tinge of the ozonized solution. 

Partially close the air ports at the base of the barrel, turn the gas on full, hold the sparker about 5 cm above the top of the barrel, and proceed to light. Adjust the gas valve until the flame extends about 8 cm above the barrel. Adjust the air supply until you have a quiet, steady flame with a sharply defined, light-blue inner cone. If an internal flame develops, turn off the gas valve, and let the burner cool down. Otherwise, the metal of the burner can get hot enough to set fire to anything nearby that is flammable. Before you relight the burner, partially close the air ports. 

Two ozone bands situated near 9.5 microns in the infrared (1) show considerable absorption, near 50% for a single atmosphere, but are markedly temperature and pressure sensitive. This property is useful in certain work as will be noted below. Finally, ozone exhibits some absorption in the visible spectrum, in particular within the yellow-orange region, resulting in giving the gas a light blue color when viewed in bulk. This absorption is weak but may be used to supplement or check experimental work which employs the ultraviolet bands. 

When hydrogen gas was introduced into argon plasma jet, all the argon emissions were strongly quenched and a very short and brilliant flame with a light blue color was formed. The emissions from excited hydrogen atoms (E 12 eV) and molecules (E 11.8eV) were... 

When ammonia gas was introduced into an argon plasma jet at a flow rate of 60 seem, all argon emission lines disappeared, and a very short but brilliant light blue flame was formed. A very strong NH emission... 

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