Question 1

​Of the following fuel gases, which has the fastest burning velocity?

Accepted Answer

Hydrogen has the fastest burning velocity among the given fuel gases due to its small molecular structure and low density.

Question 2

​The higher the combustion rate of an oxygen fuel mixture, the more prone the mixture is to ____.

Accepted Answer

Flashback is the phenomenon where the flame propagates back through the fuel supply line into the mixture tank. This typically occurs due to a high combustion rate, which causes the flame to travel faster than the fuel can flow. Therefore, the higher the combustion rate of an oxygen fuel mixture, the more prone it is to flashback.

Question 3

​The number of oxygen atoms required to completely combust the fuel gas ____.

Accepted Answer

The number of oxygen atoms required for complete combustion depends on the molecular makeup of the fuel gas, as different compounds require different amounts of oxygen to fully react.

Question 4

​Of the following fuel gases, which has the slowest burn rate?

Accepted Answer

The answer of ​Of the following fuel gases, which has...

Question 5

​Hydrocarbons are made up of ____.

Accepted Answer

Hydrocarbons are organic compounds made up of only hydrogen and carbon atoms.

Question 6

​A molecule of acetylene is made up of ____.

Accepted Answer

A molecule of acetylene consists of two hydrogen atoms and two carbon atoms, arranged in a linear fashion with a triple bond between them.

Question 7

​The final products of all clean-burning hydrocarbon flames are ____.

Accepted Answer

The final products of all clean-burning hydrocarbon flames include water vapor and carbon dioxide. This occurs because the hydrocarbon molecules react with oxygen during the combustion process, producing these two compounds as waste products. Option A is incorrect as it omits the presence of hydrogen in the final products. Option B only identifies the final products of hydrogen flames, which do not burn hydrocarbons. Option C also fails to include carbon dioxide as a product.

Question 8

​Acetylene is unstable at pressures above ____ psig.

Accepted Answer

Acetylene becomes unstable and can decompose explosively at pressures above 30 psig, which is why it must be handled with care at lower pressures.

Question 9

​What is the finished flame product of reducing oxyhydrogen?

Accepted Answer

Reducing oxyhydrogen results in the formation of water as the end product. This is because oxyhydrogen is a mixture of hydrogen and oxygen gases in a 2:1 ratio. When these gases are reduced, they combine to form water (H2O).

Question 10

Oxygen manifolds must be at least ____ feet away from fuel gas manifolds.

Accepted Answer

The answer of Oxygen manifolds must be at least ____...

Question 11

​The withdrawal rate of gas from a cylinder should not exceed ____ of the total cylinder capacity per hour.

Accepted Answer

The withdrawal rate of gas from a cylinder should not exceed one-seventh of the total cylinder capacity per hour to ensure safety and prevent excessive pressure drop.

Question 12

​A molecule of propane is made up of ____.

Accepted Answer

Propane is a hydrocarbon with the chemical formula C3H8, meaning it consists of three carbon atoms and eight hydrogen atoms.

Question 13

​Suppose the inner cone of a flame produces 430 Btu per cubic foot of gas, and the outer envelope produces 610 Btu per cubic foot of gas.What is the total heat produced by the flame?

Accepted Answer

The total heat produced by the flame is the sum of the heat produced by the inner cone and the outer envelope: 430 Btu + 610 Btu = 1040 Btu per cubic foot.

Question 14

​Combining calcium carbide and water produces ____.

Accepted Answer

Calcium carbide and water react to produce acetylene gas and calcium hydroxide.

Question 15

​Acetylene is produced by mixing ____.

Accepted Answer

Acetylene is produced by the reaction of calcium carbide (CaC2) with water (H2O). This reaction produces acetylene gas (C2H2) and calcium hydroxide (Ca(OH)2) as a byproduct.

Question 16

​A homogeneous mixture of 50% acetylene and 50% oxygen has a burn rate of ____ feet per second.

Accepted Answer

The burn rate of a homogeneous mixture of 50% acetylene and 50% oxygen is 22.7 feet per second. This specific mixture ratio allows for a very efficient and fast combustion process, which is reflected in the high burn rate.

Question 17

​Acetylene is unstable at temperatures above ____ Fahrenheit.

Accepted Answer

Acetylene becomes unstable and can decompose explosively at temperatures above 1435°F.

Question 18

​Acetone absorbs about ____ times its own weight in acetylene.

Accepted Answer

Acetone can absorb about 24 times its own weight in acetylene, which makes it an effective solvent for storing and transporting acetylene gas. This property is important because acetylene is a highly flammable gas and can pose safety risks if not stored properly. Acetone is used in acetylene cylinders to absorb and stabilize the gas, preventing decomposition and reducing the risk of explosion.

Question 19

​If more than one torch is to be used with a cylinder, the draw rates of the tips should be ____ to obtain the number of cylinders that must be manifolded together.

Accepted Answer

The draw rates of the tips should be added together to determine the total draw rate required, which helps in calculating the number of cylinders needed.

Question 20

​The heat produced by the secondary flame of an MPS gas is about ____ the heat of acetylene.

Accepted Answer

The secondary flame of an MPS gas produces about twice the heat of acetylene.

Quiz 31: Oxyfuel Welding and Cutting Equipment, Setup, and Operation

​Of the following fuel gases, which has the fastest burning velocity?

​The higher the combustion rate of an oxygen fuel mixture, the more prone the mixture is to ____.

​The number of oxygen atoms required to completely combust the fuel gas ____.

​Of the following fuel gases, which has the slowest burn rate?

​Hydrocarbons are made up of ____.

​A molecule of acetylene is made up of ____.

​The final products of all clean-burning hydrocarbon flames are ____.

​Acetylene is unstable at pressures above ____ psig.

​What is the finished flame product of reducing oxyhydrogen?

Oxygen manifolds must be at least ____ feet away from fuel gas manifolds.

​The withdrawal rate of gas from a cylinder should not exceed ____ of the total cylinder capacity per hour.

​A molecule of propane is made up of ____.

​Suppose the inner cone of a flame produces 430 Btu per cubic foot of gas, and the outer envelope produces 610 Btu per cubic foot of gas.What is the total heat produced by the flame?

​Combining calcium carbide and water produces ____.

​Acetylene is produced by mixing ____.

​A homogeneous mixture of 50% acetylene and 50% oxygen has a burn rate of ____ feet per second.

​Acetylene is unstable at temperatures above ____ Fahrenheit.

​Acetone absorbs about ____ times its own weight in acetylene.

​If more than one torch is to be used with a cylinder, the draw rates of the tips should be ____ to obtain the number of cylinders that must be manifolded together.

​The heat produced by the secondary flame of an MPS gas is about ____ the heat of acetylene.

Of the following fuel gases, which has the fastest burning velocity?

The higher the combustion rate of an oxygen fuel mixture, the more prone the mixture is to ____.

The number of oxygen atoms required to completely combust the fuel gas ____.

Of the following fuel gases, which has the slowest burn rate?

Hydrocarbons are made up of ____.

A molecule of acetylene is made up of ____.

The final products of all clean-burning hydrocarbon flames are ____.

Acetylene is unstable at pressures above ____ psig.

What is the finished flame product of reducing oxyhydrogen?

The withdrawal rate of gas from a cylinder should not exceed ____ of the total cylinder capacity per hour.

A molecule of propane is made up of ____.

Suppose the inner cone of a flame produces 430 Btu per cubic foot of gas, and the outer envelope produces 610 Btu per cubic foot of gas.What is the total heat produced by the flame?

Combining calcium carbide and water produces ____.

Acetylene is produced by mixing ____.

A homogeneous mixture of 50% acetylene and 50% oxygen has a burn rate of ____ feet per second.

Acetylene is unstable at temperatures above ____ Fahrenheit.

Acetone absorbs about ____ times its own weight in acetylene.

If more than one torch is to be used with a cylinder, the draw rates of the tips should be ____ to obtain the number of cylinders that must be manifolded together.

The heat produced by the secondary flame of an MPS gas is about ____ the heat of acetylene.