KOH added : 7.5 ml
<h3>Further explanation</h3>
Buffer solution of weak acid HCOOH and strong base KOH
Reaction
initial = 100 ml 0.1 M HCOOH = 10 ml mol HCOOH, and x mlmol of KOH
KOH + HCOOH ⇒ COOHK + H₂O
x 10
x x x x
- 10-x x x
[HCOO - ] = 3[HCOOH]

It will change because of the heat
Is there supposed to be a graph or something?
Answer: an electron of an atom, located in the outermost shell (valence shell) of the atom, that can be transferred to or shared with another atom.