In general terms, exothermic reactions release energy, so the energy goes from the system to the surroundings.
If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.
If the angle is 45, then there is still some work involved.
The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90.
iron Presence of trace elements, irradiation and iron impurities give the gem amethyst its purplish color!
Definitely not D i would guess A or B
Answer:
An acid dissociation constant, K a, (also known as acidity constant, or acid-ionization constant) is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction ↽ − − ⇀ − + + known as dissociation in the context of acid–base reactions.
Explanation: