Welders use helium (He) and argon (Ar) gases to blow over the metal during the welding process. Why would they want to use these gases?

Md Ariful Islam

0 like 0 dislike
1 views
Share with your friends

1 Answers

Md Ariful Islam

Call

In arc welding, a large potential difference is imposed between the arc tip and the welding site: the welding site becomes HOT, and melts. In the absence of inert gas, the welding site would rapidly oxidize; in the presence of inert gas, the arc tip (usually tungsten) and the welding site are protected from aerial oxidation.

Inorganic chemists regularly use argon gas for this reason. To protect reactive chemicals from oxidation. Argon and helium, as (reasonably) inert gases, are supremely unreactive, and tend not to be oxidized. Of course, under the high temperature conditions of arc welding, oxidation would be very rapid in the absence of the inert gas.

Argon is a good gas for both welders and chemists inasmuch as it is denser than air (i.e. argon is heavy!), and tends to displace the reactive gases.

0 like 0 dislike
1 views
Talk Doctor Online in Bissoy App
How many helium atoms are there in a helium blimp containing 535 kg of helium?

We work out (i) the molar quantity of helium gas.... $"Moles of helium"=(535*kgxx10^3*g*kg^-1)/(4.0*g*mol^-1)=133750*mol.$ And then (ii) we mulitply this molar quantity by Avogadro's number....$N_A=6.022xx10^23*mol^-1$ to get the number of helium...

1 Answers 1 views
A weather balloon holds 2,000 cubic meters of helium. The density of helium is 0.1765 kilograms per cubic meter. How many kilograms of helium does the balloon contain?

$rho,"density"="Mass"/"Volume"$ And thus $"Mass"$ $=rhoxx"volume"$ And here, $"Mass"$ $=$ $0.1765*kg*m^-3xx2000*m^3$ $=353*kg$

1 Answers 1 views
Argon has three naturally occurring isotopes: argon-36, argon-38, and argon-40. Based on argon's reported atomic mass, which isotope do you think is the most abundant in nature?

The mass of Argon on is 39.948. The periodic table's is the AVERAGE weight of ALL its . If one isotope is MORE abundant than the others, the average will...

1 Answers 1 views
Do ionic bonds occur between metal and non-metal ions, non-metal and non-metal ions, or metal and metal ions?

Ionic bonds occur between anions and cations. And cations may be metallic, i.e., $M^(2+)$, or they may be non-metallic, i.e. ammonium salts, $NH_4^+$. And anions, while typically non-metallic, i.e. $X^-$...

1 Answers 1 views
A sample of argon has a volume of 205 $cm^3$ when it's temperatures is -44 degrees C. and its pressure is 712 mm of Hg. What would be the volume of the argon at STP?

$T$ is always expressed as $"temperatura assoluta"$, which sets at $0*K-=-273.15$ $""^@C$. And depending on your syllabus, $STP$ specifies a temperature of $273.15*K$, and a pressure of $1*atm$. And we...

1 Answers 1 views
Consider a steel container filled with 40.0 g of helium gas and 40.0 g of argon gas. What is the ratio of pressures that each gas exerts (helium:argon)? a) 1:1 b) 10:1 c) 1:10 d) 9:1

The answer is b) 10:1. When dealing with gas , it's important to remember that the of the gases that make up the mixture depend on the number of...

1 Answers 1 views
A mixture of helium and neon gases is collected over water at 28.0°C and 745 mmHg. If the partial pressure of helium is 368 mmHg, what is the partial pressure of neon?

The partial pressures are additive; but to solve the problem we need 1 more parameter, $P_"SVP"$, the $"saturated vapour pressure"$, which is the $"vapour pressure"$ of water at the given...

1 Answers 1 views
A cylinder is filled with 200 moles of nitrogen, 300 moles of argon, and 5.00 moles of helium. If the gas mixture is at STP, what is the partial pressure of the argon?

$P_"Ar"=n_"Ar"/(n_"dinitrogen"+n_"Ar"+n_"He")xxP_"gaseous mixture"$ $=(300*mol)/(200*mol+300*mol+5*mol)xx1*"bar"$ $=300/505xx1*"bar"$ I leave ti to you to decide what is $STP$. Different syllabus has different requirements.

1 Answers 1 views
A tank contains a mixture of helium, neon, and argon gases. lf the total pressure in the tank is 490. mmHg and the partial pressures of helium and argon are 21.5 mmHg and 10.2 mmHg, respectively, what is the partial pressure of neon?

And so... $P_"Total"=P_"He"+P_"Ne"+P_"Ar"=490*mm*Hg$ But we are given that $P_"He"=21.5*mm*Hg$, and that $P_"Ar"=10.2*mm*Hg$.. And so...$P_"Ne"={490-21.5-10.2}*mm*Hg}=458.3*mm*Hg$..

1 Answers 1 views
A gas tank holds a homogeneous mixture of 0.1 mol neon, 0.2 mol helium, O.2 mol oxygen and 0.8 mol argon. Which of these gases is the solvent in this mixture?

As you know, a solution is made up of a and one or more solutes. You can distinguish between a solvent and a by looking at how much...

1 Answers 1 views
X