In a container of negligible mass, 0.0400 kg of steam at 100deg celsius and atmospheric pressure is added to 0.0200 kg of waterat 50 deg celsius. a) if no heat is lost to the surroundings, whatis the temperature of the system? b) at the final temperature, howmany kilograms are there of steam and how many of liquidwater?

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bahaistag · Accepted Answer

Latent heat of vapourisation of steam    L=540kcal/kg-C    specific heat of water    c=1kcal/kg-C    ....C is degree celsius  heat given out by steam    =mL    heat taken by water is    =mc△t    Let x kg of steam be condensed .  heat lost by x kg steam at 100 degrees C = heatgained by 0.02kg water for a temp rise from 50 to 100 degreesC    540x=0.02×1×(100−50)    x=0.02×50540=0.00185kg    Steam still remaining is 0.04 - .00185 = 0.03815 kg at 100degrees celsius  and the water is 0.02+ 0.00185 = 0.02185 kg

Jeffrey Jordon · Accepted Answer

When adding the steam to the water its temperature decrease and start to condensed. and the heat energy at thermal equilibrium equal zero  Qw+Qs=0  m×c×δT+[−m×Lv]=0  m×c×δT=ms×δT  0.2 kg×4190J/kg⋅K×[T−50]=0.04 kg×2256×106 J/kg  [T−50]=0.04 kg×2256×106 J/kg0.2 kg×4190 J/kg⋅K  T=157∘  This means that all the steam that absorbed by the water and this not true because not all the steam couldn&#039;t convert to water so the final temperature would be 100 C∘  b) To calculate the mass of the two element  Q=ms×Lv , by solving for ms which converted   ms=QLv  =4.19×104 J2256×103 J/kg  =0.0186 kg  Where 4.19×104 J is the heat absorbed by the water could calculate from Q=[m×C×δT]w  The mass of the converted water to steam is 0.0186 ,,kg  Now to calculate the steam still there without converted to water it would be  0.0400−0.0186=0.0214 kg  And for the water still in the container we would sum the mass of the water and the condensed steam to calculate the total mass of water  mw=0.0186+0.2  =0.219 kg

In a container of negligible mass, 0.0400 kg of steam at 100deg celsius and atmospheric pressure is added to 0.0200 kg of waterat 50 deg celsius. a) i

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