The terrifying energy inside a bomb calorimeter #science #chemistry #shorts

本站添加: 2026-06-04

[00:00:00]Internal energy.

[00:00:02]When a change occurs in a chemical system, to know how much energy is released or absorbed, we need a quantity representing total energy of that system.

[00:00:11]It is the sum total of chemical, [music] electrical, mechanical, and all other energies of that system.

[00:00:18]>> [music] >> That quantity is called internal energy.

[00:00:21]It is represented by symbol U.

[00:00:25]Bomb calorimeter delta U measurements.

[00:00:28]>> [music] >> In chemical reactions, heat absorbed at constant volume is measured in a bomb calorimeter.

[00:00:34]Bomb calorimeter is placed in a water bath.

[00:00:37]>> [music] >> This whole arrangement is called calorimeter.

[00:00:40]Bomb calorimeter is thermally insulated.

[00:00:43]Therefore, there is [music] no heat exchange from calorimeter to surroundings.

[00:00:47]During reaction, calorimeter is kept completely closed. [music] Therefore, there is no change in its volume.

[00:00:54]At constant volume, delta [music] V is equal to zero.

[00:00:57]W is equal to P delta V. That is equal to zero. That means no work is done.

[00:01:04]Using the increase in temperature [music] of calorimeter due to reaction, the heat evolved can be calculated from mass of calorimeter [music] and its heat capacity values through this equation.

[00:01:16]Q is [music] equal to C delta T.

[00:01:21]Delta H measurements.

[00:01:23]Since atmospheric pressure remains constant, the heat change produced by reaction [music] in calorimeter can be considered as measured at constant pressure.

[00:01:32]QP is equal to delta H.

[00:01:36]Therefore, heat change measured at constant pressure >> [music] >> becomes heat of reaction or enthalpy of reaction, delta small r H.

[00:01:45]Heat is given from system to surroundings. [music] Therefore, QP is negative and delta small r H is negative.

[00:01:54]If heat is absorbed, [music] QP and delta RH is positive.