phan tir CH3COOH bj phan li tang, nhung do so phan tir CH3COOH hoa tan tang(them CH3COO vao). Do do do dien li a tang hay giam chUa xac djnh duoc.loang dung djch, do dien li a cQa dung djch chat dien li ye'u tang.
Giai thfch: Kc = CQ.= const (nhiet do xac dmh)
1a'>: ''. ,De Kc = c[r]