1.

Calculate the heat required to convert 3 kg of ice at -12" "^(@)C kept in a calorimeter to steam at 100" "^(@)C at atmospheric pressure. Given specific heat capacity of ice =2100" J kg"^(-1)K^(-1), specific heat capacity of water =4186" J kg"^(-1)K^(-1), latent heat of fusionn of ice =3.35xx10^(5)" J kg"^(-1) and latent heat of steam =2.256xx10^(6)" J kg"^(-1).

Answer»

Solution :Mass of ice `m=3` kg
Specific heat of ice `S_("ice")=2100" Jkg"^(-1)K^(-1)`
Specific heat of water `S_(W)=4186" Jkg"^(-1)K^(-1)`
Latent heat of fusion of ice `L_(F"(ice)")=3.35xx10^(5)" Jkg"^(-1)`
Latent heat of VAPORIZATION of steam `L_("heat")=2.256xx10^(6)" Jkg"^(-1)`
`rArrQ_(1)=` heat required to rise temperature of ice from `-12^(@)C` to `0^(@)C`
`="mS"_("ice")DeltaT_(1)`
`=3xx2100xx[0-(-12)]`
`=6300xx12`
`:.Q_(1)=756000" J. . . (1)"`
`rArr Q_(2)=` heat required to CONVERT ice of `0^(@)C` in to water
`=mL_("ice")`
`3xx3.35xx10^(5)`
`:.Q_(2)=1005000 " J. . .(2)"`
`rArrQ_(3)=` heat required to rise temperature of water from `0^(@)C` to `100^(@)C`
`=mS_(W)DeltaT_(2)`
`=3xx4186xx(100-0)`
`:.Q_(3)=1255800" J. . .(3)"`
`rArr Q_(4)` = heat required to convert water of `100^(@)C` in to steam
`=mL_("steam")`
`=3xx2.256xx10^(6)`
`:.Q_(4)=" 6768000" J. . .(4)"`
`rArrQ=` heat required to convert ice at `-12^(@)C` in to steam
`:.Q=Q_(1)+Q_(2)+Q_(3)+Q_(4)`
From equation (1), (2), (3) and (4)
`Q=75600+1005000+1255800+6768000=9104400" J"`
`:.Q~~9.1xx10^(6)J`


Discussion

No Comment Found