Final answer:
In step 4 of setting up an oxyacetylene torch, stand to the side and slowly turn on the acetylene or fuel gas cylinder valve, opening it 1/4 to 3/4 of a turn. As for burning the acetylene, considering the equation 2C₂H₂ + 5O₂ -> 4CO₂ + 2H₂O, about 3.33 tanks of oxygen would be needed for one acetylene tank of 9340 liters.
Step-by-step explanation:
In step 4 of setting up your oxyacetylene torch, you should Stand to the side and slowly turn on the acetylene or fuel gas cylinder valve. Open it approximately 1/4 to 3/4 of a turn, or slightly more if necessary to get a good reading. This is because you want to make sure the gas is flowing smoothly and at the correct rate.
Now, about the related question on how many oxygen tanks are required to burn the acetylene, considering the equation 2C₂H₂ + 5O₂ -> 4CO₂ + 2H₂O, for every 2 moles of acetylene, 5 moles of oxygen are required. Consequently, if an acetylene tank provides 9340L of gas (1 mole of gas at standard temperature and pressure (0°C, 1 atm) occupies 22.4L), thus 9340/22.4≈417 moles of acetylene gas are in one tank. Considering the 2:5 ratio, you'll need 1042.5 moles of oxygen. If each tank of oxygen provides 7000 liters of gas (≈313 moles), then you'll need around 3.33 tanks.
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