Question

A bomb calorimeter is used to measure the value of heat of reaction at a constant
A. Volume
B. Pressure
C. Temperature
D. None of these

Answer 1

Hint: In this question, we are discussing a bomb calorimeter (It is a device that is designed to measure the amount of heat that is given off or taken in by a reaction). So, here we have to identify the constant quantity at which this calorimeter works.

Complete step by step answer:
Calorimetry is the technique used to measure the amount of heat through the measurement of change in temperature, and can be used to determine the heat of a reaction in any experiment.
Usually a Coffee-Cup Calorimetry is used due to its simplicity than a bomb calorimeter, but to measure the heat given out in a combustion reaction, constant volume is required for which a bomb calorimetric is ideal.
 A constant volume calorimeter measures the heat more precisely than a coffee-cup calorimeter, but is difficult to use as it requires a well-built reaction container so that when there is a change in the value of pressure in the chemical reaction , it can withstand that change .

A simplified bomb calorimeter.
At a constant volume in a bomb calorimeter, the system is sealed and isolated from its surroundings, which accounts for why its volume is fixed and thus there is no volume-pressure work done.
A bomb calorimeter structure consists the following components:
-Steel bomb which contains all the reactants
-Water bath in which the bomb is immersed
-Thermometer
-A motorized stirrer
-Wire for ignition
Since the process takes place at constant volume, The vessel is usually called a “bomb”, and the technique is known as bomb Calorimetry.
The reaction starts by discharging a capacitor through a thin wire which ignites the mixture.
So, the correct answer is “Option A”.

Note: While using a bomb calorimeter, a very high amount of heat energy is given out . So the reaction mixture vessle must be constructed to adhere to the high pressure resulting from the combustion process, which amounts to almost a confined explosion.