The heat exchange in chemical reactions is due to a change in:

A. kinetic energy
B. enthalpy
C. temperature
D. physical properties

B

Explanation:

This would be due to enthalpy. This is because that this where heat exchange happens in chemical reactions.

So, a positive enthalpy means that the reaction is endothermic (heat entering) and if enthalpy is negative this will be a exothermic (heat released)

Another example would be the use of atoms. This example if temperature is the factor, this means that at low temp there is less kinetic energy so low temperature. However, an increase in energy means that there is more kinetic energy in the atoms which means that more collisions occurring.

Hope this helps

Have a nice day :)

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.