10 g of a fuel is combusted in the internal chamber of a bomb calorimeter because of which the temperature of 250 g of the water present in external chamber increases from `25^(@)C" to "75^(@)C`. Write the following steps in a sequential order to find the value of calorific value of the fuel. (Assume that the heat produced by the combustion of fuel is completely absobed by the water).
(a) Equate `m_(F)S=m_(u)S_(w)(Delta t)` and find the value of S.
(b) Note the value of mass of fuel `(m_(F))` and water `(m_(w))` in bomb calorimeter from the given data.
(c) Consider the change in the temperature `(Delta t)` of the water to find the heat absorbed by water using, `Q=m_(u)S_(w)(Delta t)`.
(d) Let 'S' be the calorific value of the fuel and heat produced by the combustion of the fuel is given by `Q=m_(f)S.`

Options

A. abcd
B. bcad
C. bcda
D. cbad

Answer

C

Explanation

`m_(w)=250 g, m_(F)=10 g, S_(w)=1 cal g^(-1)""^(@)C^(-1)(b)`
`Deltat=(75-25)^(@)C=50^(@)C` Heat absorbed by water `=m_(w)s_(w)(Deltat)=250xx1xx50`
`=12500` cal (c)
The heat liberated by the fuel,
`Q_("produced")=m_(F)S=10 S(d)`
`"We Know "Q=m_(F)S=m_(w)s_(w)(Deltat)`
`rArrs(m_(w)s_(w)(Deltat))/(m_(F)).(a)`
`S=(12500" cal")/(10 g)=1250 cal g^(-1)`