Gases reacting volumes

It may be recalled that in homogeneous reactions all reacting materials are found within a single phase, be it gas, liquid or solid if the reaction is catalytic, then the catalyst must also be present within the phase. Thus, there are a number of means of defining the rate of a reaction the intensive measure based on unit volume of the reacting volume (V) is used practically exclusively for homogeneous systems. The rate of reaction of any component i is defined as... 

Aluminum metal reacts with HC1 to produce aluminum chloride and hydrogen gas. What volume of hydrogen gas, at STB is produced when 13.5 g of aluminum is mixed with an excess of HC1 ... 

In what volume ratio do hydrogen gas and oxygen gas react to form water ... 

When a gaseous compound X containing only C, H, and O is burned in 02, 1 volume of the unknown gas reacts with 3 volumes of 02 to give 2 volumes of C02 and 3 volumes of gaseous H20. Assume all volumes are measured at the same temperature and pressure. 

His research led him to devise the law of combining volumes When gases react, the volumes of the reactants and the products, measured at equal temperatures and pressures, are always in whole number ratios. For example, 2 volumes of hydrogen gas react with 1 volume of oxygen gas to produce 2 volumes of water vapour. 

By combining these ideas, Avogadro related the volume of a gas to the amount that is present (calculated from the mass). Avogadro divided Dalton s mass ratios by the molar masses of the elements to obtain the mole ratios. He realized that these mole ratios were the same as the volume ratios that Gay-Lussac had obtained. For example, 1 L of hydrogen gas reacts with 1 L of chlorine gas. Avogadro decided that there must be the same number of molecules in each litre of gas. Thus, Avogadro s hypothesis was formulated Equal volumes of all ideal gases at the same temperature and pressure contain the same number of molecules. 

This information will help you with a certain type of gas stoichiometry problem. When a gas reacts to produce another gas, you can use Gay-Lussac s law of combining volumes to find the volumes of the gases. The following Sample Problem shows you how. 

Methanol. As is the case with ethanol, the concept of producing methanol from wood is not new. Methanol obtained from the destructive distillation of wood represented the only commercial source until the 1920s. The yield of methanol from wood by this method is low, only about 1-2 percent or 20 L/metric ton (6 gal/ton) for hardwoods and about one-half that for softwoods. With the introduction of natural gas technology, the industry gradually switched to a synthetic methanol formed from a synthesis gas (syngas) produced from reformed natural gas. Two volumes of H2 and one volume of CO are reacted in a catalytic converter at pressures of 1500-4000 psi to produce methanol. Presently, 99 percent of the methanol produced in the United States is derived from natural gas or petroleum. 

Pi = peak pressure of the reacting gas mixture in a gas-tight volume p0 = initial pressure of the gas mixture... 

When water decomposes into its elements—hydrogen and oxygen gas—the volume of hydrogen produced is always twice the volume of oxygen produced. Because matter is conserved, in the reverse synthesis reaction, the volume of hydrogen gas that reacts is always twice the volume of oxygen gas. 

Observation The carbon pieces light up and show a strong exothermic reaction with oxygen, until they completely disappear. The volume of 100 ml gas in the piston sampler remains intact. When the gas reacts with the lime-water, a white deposit precipitates. 

Prefer monolithic confignration for intensification with surface area/volume usually 1.5 to 4 times greater than traditional pellets. Excellent for mass transfer controlled reactions. For gas reacting with solid nsnally heat transfer controlled, because these are highly exothermic or endothermic reactions. Particle size and size distribution are critical. These reactions may follow different patterns ... 

It has been shown experimentally01 that with a 1 1 mixture of carbon monoxide and hydrogen passed over a supported nickel catalyst at 290° to 340° C., 80 per cent of the carbon monoxide reacted to form methane by equation (a) and only 20 per cent by equation (b). No carbon was deposited in this temperature range and a time of contact of 10 seconds gave the maximum conversion. Very little reaction occurred below 290° C. Increasing space velocity favored reaction (b) in the presence of sugar charcoal-pumice-vauadium pentoxide-nickel catalysts although even with a space velocity of 1500 volumes of gas per volume of catalyst per hour only 20 per cent of the methane was formed by reaction (b).70... 

Francis calculations 118 have shown that per volume of water-gas reacted, considering hydrogen and carbon monoxide as equivalent, the formation of carbon dioxide is accompanied by the largest free energy... 

Equation (5.5) is the mathematical expression of Avogadro s law, which states that at constant pressure and temperature, the volume of a gas is directly proportional to the number of moles of the gas present. From Avogadro s law we learn that when two gases react with each other, their reacting volumes have a simple ratio to each other. If the product is a gas, its volume is related to the volume of the reactants by a simple ratio (a fact demonstrated earlier by Gay-Lussac). For example, consider the synthesis of ammonia from molecular hydrogen and molecular nitrogen ... 

EXAMPLE 16 (fl) If 6.00 L of hydrogen gas reacts with oxygen gas to form liquid water, what volume of oxygen will react, assuming that the oxygen is measured at the same temperature and pressure as the hydrogen, (b) Can the volume of the water be determined ... 

Decrease volume (increase pressure). Because four moles of gas react to form two moles of gas, decreasing the volume will shift the equilibrium position toward fewer moles of gas, that is, toward forming more NH3. 

Nitrogen gas reacts with hydrogen gas to form ammonia gas. You have an equimolar mixture of nitrogen and hydrogen gases in a 15.0-L container fitted with a piston in a room with a pressure of 1.00 atm. The piston apparatus allows the container volume to change in order to keep the pressure constant at 1.00 atm. Assume ideal behavior, constant temperature, and complete reaction. 

Since one moie of gas occupies 22.4 dm at s.t.p., rlicgus moUt volume is 22.4 at s.t p. This makes calculations on reacting volumes of gases very simple. An equation which shows how many moles of different gases react together also shows the ratio of the volumes of the different gases that react together. For example, the equation... 

In an experiment (in which aU gases were at the same temperature and pressure before and after reaction) it was found that 1.21 dm of hydrogen gas reacted completely with 1.21dm of chlorine gas to produce 2.42 dm of hydrogen chloride. Using Avogadro s law, explain whether or not these volumes confirm the equation... 

---