1. HCl is a strong acid, so it will completely dissociate in water to form H+ ions and Cl- ions. Therefore, the concentration of H+ ions is equal to the 0.05 M concentration of HCl.
pH = -log[H+]
pH = -log(0.05)
pH = 1.30
2. NaOH is a strong base, so it will completely dissociate in water to form Na+ ions and OH- ions. Therefore, the concentration of OH- ions is equal to the 0.05 M concentration of NaOH.
pOH = -log[OH-]
pOH = -log(0.05)
pOH = 1.30
Since pH + pOH = 14,
pH = 14 - pOH
pH = 14 - 1.30
pH = 12.70
3. H2SO4 is a diprotic acid, so it will dissociate in water to form 2 moles of H+ ions for every 1 mole of H2SO4. Therefore, the concentration of H+ ions is twice the 0.05 M concentration of H2SO4.
pH = -log[H+]
pH = -log(2 * 0.05)
pH = -log(0.10)
pH = 1.00
Calculate the pH of following solutions
1. 0.05 M Hcl
2.0.05 M NaoH
3. 0.05 M H2so4
1 answer
2 answers