Recent content by Carlo09

Ok I have an idea, Mixing bicarb and vinegar produces sodium acetate solution in water. Concentrating this by boiling off the water and then maybe making a handwarmer type solution ... supersaturated sodium acetate solution and then cause it to crystalise to heat the water? Could it work using...

Ok so I have some vinegar and Bicarb and want to generate an exothermic reaction, but just mixing them produces CO2 in an endothermic reaction! How can I do this? Thank you.

Ooo right ok so I have dw/dQ_h = (T1-T2)/T1 = 0 therefore T1-T2 = 0 so T1=T2=T and so dw/dQ_h = (T-T)/T which is 0 which doesn't help me :S

I solved it, this is what I did: From the temperature we know it's superhated steam so looking at the steam tables we can find it's specific volume, 1/Specific volume = Density, density * volume = mass So now we have the mass of the steam in the system. Now mass / final volume =...

Thank you, Which equation do I differentiate?

Are you meaning differentiate and set to 0 and then solve? Differentiate again and is D^2f(x)/Dx^2 < 0 then it's a maximum?

My work is wrong, it gives me the wrong answer. P1V1=nRT1 / P2V2=nRT2 P1V1/P2V2 =T1/T2 T2 = T1P2V2 / P1V1 and I get T2= 1146 degrees C which is Slightly too high.

Homework Statement A heat pump takes heat from a hot resevoir and dissipates heat to a cold one. Both resevoirs are equal mass and specific heat capacity. Show that as the heat engine does maximal work the final temp of the resevoirs = Tf = SQRT(TcTh) Homework Equations Qin = Wout +...

The problem sheet we have been given has the answers on it, we need to show our working as it is that which is important.

Homework Statement Ok the problem I have been set has a frictionless piston containing steam at 200kpa at 200 degrees c and it is originally at 0.5m^3. It has a linear spring above it just touching and exerting no force. Heat is added and the gas expands pushing the cylinder up and causing the...

It says the temperature of petrol is monitored by a thermocouple in the flow, so I'm guessing pipes? How did you get your Re at that value? Have i used the wrong values to calculate it? Thank you for your help

Ok it's my first time here and I was hoping to get some help on some questions I have been given. I am a first year chem eng and I'm finding the work pretty hard so any help at all will be useful, thanks. I need to find the convective heat transfer coefficient, h for petrol using this...