Steam Question Answer

Steam table question?

Try using a plastic 3/4 cover, available from restaurant supply for use on steam tables. That will help keep it from drying out.

As long as the casserole does not have a crust or topping - turning it on a regular basis will help reincorporate liquid that is moving to the top and thus being turned into steam.

Depending on how much water you have to add, it may affect the flavor negatively. A fatty ingredient (milk, butter, oil, etc) will help keep the casserole moist as it will not evaporate - but that also would impact flavor and she might need to rework the recipe.

And lastly - not every recipe belongs on a steam table. Some things recipes are not durable enough to be held a long time at serving temperature. This may be the case with your Mom's squash casserole.

Congrats on opening a new restaurant. It is a lot of hard work, but it can be a lot of fun, too!

I hope that helps.

Steam distillation questions.....?

Because the distillate contains both water and your compound, the vapor pressure of your compound can be below one atmosphere at the boiling point of the mixture. (Raoult's Law)

Normally compounds below 100 C do not need to be steam distilled because they can be distilled directly without decomposition.

For steam distillation to work, the compound must be insoluble or only sparingly soluble in water, not subject to hydrolysis (you can't steam distill an acid chloride), and sufficiently volatile at 100 C to ensure practical recovery.

Steam powered rocket quick question?

A rocket with mass M is sitting motionless in space. The rocket is powered by steam with velocity Vs and mass per time C = dm/dt. Write an equation for rocket acceleration in terms of M, VS, and C.

I know to equate the force on the steam to the force on the rocket because of newton's 3rd law so: F(steam)=F(rocket). Then I use newton's second law in the form F= d(mv)/dt. Using the chain rule I get m(steam)*dV(steam)/dt + V(steam)*dm(steam)/dt = M(rocket)*dV(rocket)/dt + V(rocket)*dM(rocket)/dt...I know that the mass of the rocket is not going to change so the V(rocket)*dM(rocket)/dt term drops out. I have the solution so I know that the m(steam)*dV(steam)/dt also drops out and my question is why? Is it because the mass of the steam is negligible compared to the mass of the rocket and m(steam) = 0? Or is it that the steam doesn't have any acceleration and the dV(steam)/dt term = 0? Thanks in advance.

Steam distillation questions....?

For example, the isolation of aniline, C6H5NH2, by steam distillation. At 100C, the vapor pressure of water is 760mmHg. The vapor pressure of aniline is "x" at 100C. The vapor pressure of the mix is (760-x) + (x) at 100C. "x" is the vapor pressure of aniline if it were boiling at a much lower temperature. It is like vacuum distillation without the vacuum.

It is important that aniline is "insoluble" in water. Because after the steam distillation, one can extract the aniline from the water with organic solvents.

I do not know three characteristics, but I can point out one example: ortho-nitrophenol and para-nitrophenol. One separates them by steam distillation. The ortho-isomer is hydrogen bonded internally and so volatile with steam. The para-isomer is not, and so stays behind.

Thermodynamics & Heat Transfer question... Steam efficiency etc..?

A power plant taps steam superheated by geothermal energy to 505 K (the temperature of the hot reservoir) and uses the steam to do work in truning the turbine of an eletric generator. The steam is then converted back into water in a condenser at 323 K (the temperature of the cold reservoir), after which the water is pumped back down into the ground where it is heated again. The output of the generator is 84MW. Calculate:
The maximum efficiency at which this plant can operate.

The minimum amount of rejected heat (in MJ) that must be removed from the condenser every 24 hours.

Would appresiate if you showed working with the answer so i can work though it myself, but just the answer is fine. Cheers :)