C. combustion I think. hope this helps
Answer: 25N
method: total force in the right hand direction is 100N and total force in the left hand direction is 125N. To get the net force, we add forces if they are in the same direction and substract if they are in opposite directions. since 100N and 125N are in opposite directions, we substract the larger value from the smaller value. Then we get 25N in the left hand direction as the final answer.
pH is the measure of the concentration of hydrogen ions in a solution
C it is the energy required to break existing chemical bonds, it is the amount of energy that a reaction requires in order for the reactants to successfully collide and react
