Question

The heat measured for a reaction in bomb calorimeter is:
(A) ${ \Delta G }$
(B) ${ \Delta H }$
(C) ${ \Delta U }$
(D) ${ P\Delta V }$

Answer 1

Hint: A calorimeter is an instrument used to quantify heat changes in a reaction. It is an instrument that is utilized for calorimetry (a procedure to gauge the vitality changes related to physical or substance changes).

Complete step by step answer:
The bomb calorimeter comprises fundamentally of the example, oxygen, the hardened steel bomb, and water.
The dewar prevents heat stream from the calorimeter to the rest of the universe, i.e,
${ q }_{ calorimeter }{ =0 }$
Since the bomb is produced using tempered steel, the ignition reaction occurs at a consistent volume and there is no work, i.e,
${ w }_{ calorimeter }{ =-\int { pdV=0 } }$
Thus, the change in internal energy, ${ \Delta U }$, for the calorimeter is zero. Thus, the change in internal energy, ${ \Delta U }$, for the calorimeter is zero.
${ \Delta U }_{ calorimeter }{ =q }_{ calorimeter }{ +w }_{ calorimeter }{ =0 }$
The bomb calorimeter is fixed so that ${ \Delta V=0 }$
furthermore, subsequently
Work done = 0
Energy changes related to the reaction are estimated at a steady volume.

After the finish of the reaction, the temperature change (${ \Delta T }$) of the calorimeter is changed over into ${ q }_{ V }$ by utilizing the connection
${ q }{ =c }_{ V }{ \Delta T }$
Where ${ c }_{ V }$ is the heat capacity of the bomb calorimeter
A bomb calorimeter is a kind of consistent volume calorimeter utilized in estimating the heat of ignition of a specific reaction.
Subsequently, the heat estimated for a reaction in bomb calorimeter is ${ \Delta U }$.

Hence, the correct option is C.

Additional Information:
-Bomb calorimeter need to withstand the enormous weight inside the calorimeter as the reaction is being estimated.
-Electrical vitality is used to touch off the fuel; it will warm up the encompassing air, which extends and escapes through a cylinder that drives the freshen up of the calorimeter.
-At the point when the air is getting away through the copper tube, it will likewise warm up the water outside the cylinder The adjustment in temperature of the water takes into account the computing the calorie substance of the fuel.
-Fundamentally, the bomb calorimeter comprises a little cup to contain, for example, oxygen, a treated steel bomb, water, a stirrer, a thermometer, the dewar or protecting the compartment, and a start circuit associated with the bomb.
-By utilizing tempered steel for the bomb, the reaction will happen with no volume change observed.

Note: The possibility to make a mistake is that in bomb calorimeter there may be a percent error in water measurement. Also, the acid correction in the bomb calorimeter is due to the heat of the formation of nitric acid.