Recent content by Carlo09

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    Generating an Exothermic Reaction with Vinegar and Bicarb

    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...
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    Generating an Exothermic Reaction with Vinegar and Bicarb

    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.
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    Solving Carnot Heat Engine: Tf = SQRT(TcTh)

    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
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    Solving Piston & Spring Homework Problem - Work, Temp & Heat Input

    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 =...
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    Solving Carnot Heat Engine: Tf = SQRT(TcTh)

    Thank you, Which equation do I differentiate?
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    Solving Carnot Heat Engine: Tf = SQRT(TcTh)

    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?
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    Solving Piston & Spring Homework Problem - Work, Temp & Heat Input

    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.
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    Solving Carnot Heat Engine: Tf = SQRT(TcTh)

    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 +...
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    Solving Piston & Spring Homework Problem - Work, Temp & Heat Input

    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.
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    Solving Piston & Spring Homework Problem - Work, Temp & Heat Input

    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...
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    Find the convective heat transfer coefficient

    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
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    Find the convective heat transfer coefficient

    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...