5 votes

How can I vaporize metals?

The easiest way to vaporize a metal is to create a filament of the metal. Heat the filament in the vacuum to its sublimation (vaporization) temperature. Alternatively, when the metal cannot be shaped ...
Jeffrey J Weimer's user avatar
5 votes
Accepted

Nylon brittleness as function of moisture content

Nylons are a class of polymers formed from di-acid and di-amine monomers. The amine groups bond with the acid groups to form amide groups, end to end. The resulting amide groups have a positive charge ...
do-the-thing-please's user avatar
5 votes
Accepted

In case of solvation , Who converts gaseous ions to aqueous ? Why do we even have gaseous but not solid ions?

We define reactions uniquely depending on the reactants and products. Here are examples related to your question. Formation: Na(s) + (1/2)Cl$_2$(g) $\rightarrow$ NaCl(s) Lattice Formation: Na$^+$(g) + ...
Jeffrey J Weimer's user avatar
4 votes

How the choice of etchant can affect the severity of hydrogen embrittlement during pickling and passivation?

The primary cause of hydrogen cracking is a susceptible matrix . Typically a carbon or low alloy steel that is hard ( > HRC 25) untempered is the primary problem. The martensitic chrome steels were ...
blacksmith37's user avatar
  • 6,144
3 votes

is it possible to achieve 1000C temperature in a cabin?

If the heating element is constantly at 100°C, there is no way it can cause the room can get warmer than 100°C. Otherwise, perpetual motion machines would be possible. If you meant the heating ...
Bob's user avatar
  • 64
3 votes
Accepted

Is it possible to use direct air capture technology for CO2 on a non-commercial level?

It is possible and this is currently being done at the OpenAir Collective. There are two direct air carbon capture (DACC) machines under active development, Violet and Cyan. Both are small-scale, open-...
Dahl Winters's user avatar
3 votes
Accepted

Help with Mass Flow Rate

It's the density calculation you have. You're almost there! This site explains it pretty well: https://www.engineeringtoolbox.com/slurry-density-calculate-d_1188.html Density of slurry=1/[(ratio of ...
mechcad's user avatar
  • 523
2 votes

Are brass and copper utensils safe for humans to eat from?

It always depends on the concentration and where you place the copper within the human body. In my opinion, the most interesting example are implants which are coated with copper and implanted ...
h_uat's user avatar
  • 139
2 votes

is it possible to achieve 1000C temperature in a cabin?

To answer the question the way it's asked heating element of sort which is providing 100°C constantly but because room is totally insulated and shut can the temperature goes upto 1000°C or not ? ...
Nick Alexeev's user avatar
  • 1,035
2 votes

What's a good way to equalize pressure between 2 spaces without allowing gas exchange under normal circumstances?

There are specialty sensors and relays that are sensitive enough for the range of pressure you need, but they may be expensive. one way is to hang the container in balance with a ballast weight to a ...
kamran's user avatar
  • 22.4k
2 votes
Accepted

What chemical can be used to restore synthetic rubber?

The embrittlement and goop-forming reactions are fundamentally different, and different measures would be needed to deal with each. Rubber embrittlement occurs when the rubber oxidizes, and stops ...
niels nielsen's user avatar
2 votes

Can wet welding be done in mineral oil?

Mineral oil is not used to cool transformers because it is flammable. Transformer oil is a different compound which is not flammable and possesses high dielectric strength. In any case, the ...
niels nielsen's user avatar
2 votes
Accepted

Can wet welding be done in mineral oil?

No. In water welding you make steam (> hydrogen and oxygen) and conditions need to compensate for the problem of hydrogen entry in the steel. With oil you are adding the large problem of also ...
blacksmith37's user avatar
  • 6,144
2 votes
Accepted

What is the field on engineering that combines chemistry and electronics together?

You could follow either Chemistry (Science), Chemical Engineering or Electrical Engineering and purse a career in Semiconductors. There are many variation in Semiconductor that fall either into ...
Mahendra Gunawardena's user avatar
2 votes

How long will it take to anneal at a lower temperature?

The alloy makes a difference. If it is essentially copper and zinc like 70:30 (cartridge brass, or admiralty if you put in one pre-cent tin) or lower amounts of zinc: Nothing much happens with the ...
blacksmith37's user avatar
  • 6,144
2 votes
Accepted

Balancing Equation of Octane in combustion Chamber

you also need to take into account that the complete burn for octane is: $$2C_8H_{18} + 25\;O_2 \rightarrow 16\;CO_2 +18\;H_2O $$ Therefore $a$ should be equal to $\frac{25}{2}$.
NMech's user avatar
  • 24.3k
2 votes

Would the below thermal generator work properly and provide surplus energy?

Could it work? Yes. Is it practical for any scale? No. As @DKNguyen says in their comment, if you had a free source of these components you could generate this heat and use it to do things. But it ...
Tiger Guy's user avatar
  • 6,881
1 vote

How long will it take to anneal at a lower temperature?

I used a different search engine and may have found something useful. "When cold worked brass is progressively heated, the first effect, at about 250ºC, is for the internal stresses to be ...
jorkz's user avatar
  • 11
1 vote
Accepted

Difficulty in understand the meaning of standard enthalpy of formation

I prefer this definition for Hf: "The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its ...
Feynman137's user avatar
1 vote

Specific CO2-Emissions of Natural Gas & Hydrogen Mix

assuming full combustion, CO2 coming out is none from the H2 1:1 mole ratio from the CH4 So mass of CO2 = ( mass of CH4 ) x ( molar mass of CO2 ) / ( molar mass of CH4) Add a slight adjustment for ...
Pete W's user avatar
  • 1,551
1 vote

Is molecular dynamics relevant for an undergraduate Mechanical Engineering degree?

In my opinion, it is very difficult anymore to get to anything truly novel without mixing different disciplines. For example, its difficult to imagine, advances in molecular treatments, without the ...
NMech's user avatar
  • 24.3k
1 vote

What is the field on engineering that combines chemistry and electronics together?

Welcome to SE. Since your interest pertains to do very distinct field, I would recommend in taking one field as a major and the other as minor with key subjects you are interested in. Electro-...
gfdsal's user avatar
  • 129
1 vote
Accepted

Why do Blast Furnace flue dust generates high rates of Zn (Zinc)?

Not likely unless they use a very unusual ore. Blast furnaces generally do not use scrap. Scrap likely contains zinc ( die castings) . Electric arc remelt furnaces melt a high percentage of recycle ...
blacksmith37's user avatar
  • 6,144
1 vote

What is the mechanism of adsorption-desorption on biochar obtained from slow pyrolysis/ torrefaction?

I haven't done furfural desorption from biochar, but I have done furfural desorption from metals. Here are some thoughts off the top of my head. Regarding your question of furfural adsorption. I ...
Monty's user avatar
  • 131
1 vote

Why does aluminum clad steel wire have high corrosion resistance?

The dominant protection mechanism is that the aluminum excludes seawater from contact with the steel underneath, and if passivated with a layer of oxide, the corrosion rate of the aluminum via direct ...
niels nielsen's user avatar
1 vote

pH calculations for boiler water

Do they provide you with the temperature of the system? In this case what they want you to do is solve first the boiler mass balance, in case there are heat/temperature specs you could make a energy ...
Media's user avatar
  • 109
1 vote

Generic category of PBT thermoplastic

No . A more common polymer is polyethylene terepthalate ( PET) from which many bottles are made . I guess they would be the same group if it has a name.
blacksmith37's user avatar
  • 6,144
1 vote

How can I vaporize metals?

vaporizing metal in a near-vacuum is a straightforward process; the simplest method is called sputtering and is one specific method of vacuum metallization as noted by William Hird above. Keeping a ...
niels nielsen's user avatar
1 vote

Mass balance of a recycle stream

In generel for N species you have N mass balances. So in your case 2. Also mass is conserced ( other than moles when it comes to chemical reaction). So you definitely know that the mass flow rate of Y ...
Gesetzt's user avatar
  • 93
1 vote
Accepted

Calculate the radius of iridium atom, given that Ir has an FFC crystal structure, a density of 22.4 g/cm3 and atomic weight of 192.2g/mol

The radius $r$ can be calculated purely from geometry. Consider the FCC lattice. Its lattice parameter $a$ is related to radius through the arrangement of atoms. What is the close-packed direction in ...
do-the-thing-please's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible