How do I find the pH of 30 ml of H20 and 2ml of 2.0M HCl?
2007-04-19 15:08:25 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
Easy. First, find the final concentration after combining water and HCl. You know that 2mL of 2.0M HCl contains 4.0mmol HCl and combining this with water makes a final volume of 32mL. To get the concentration of H ion in the solution, 4.0mmol / 32 mL = 0.125M.
The pH is the negative log of the H ion concentration. -log of 0.125 is 0.90. That is your pH.
2007-04-19 15:47:10 · answer #1 · answered by arjay 2 · 0⤊ 0⤋
HCl is a strong acid, in other words every molecule dissociates into H+ and CL-. So you've got 2*10^-3 moles of H+ ions in about 30 mls. of water. That's 6*10^-2 moles/litre of H+. log 1/this concentration is about 1.2, which is the pH.
2007-04-19 22:21:55 · answer #2 · answered by zee_prime 6 · 0⤊ 0⤋
Avoid using a finger. Since HCl dissociates fully in water, [H+] = 2 ml x 2.0 M/32 ml = 0.125 M.
The pH of 0.125 M [H+] = 1 - log 1.25 = 0.9 appx.
2007-04-19 22:14:48 · answer #3 · answered by cattbarf 7 · 0⤊ 0⤋
litmus paper or a ph meter
2007-04-19 22:10:57 · answer #4 · answered by Todd C 4 · 0⤊ 0⤋
You can try to tongue too.
2007-04-19 22:13:57 · answer #5 · answered by slperera 3 · 0⤊ 0⤋