pH chemistry?

Question

1. urine normally has a pH of 6.0. If a patient eliminates 1800 mL of urine per day, how many moles of H+ were eliminated:
1. 1.8 x10^3 mol
2. 42 mol
3. 1.8x10^-6 mol
4. 1.8 x 10^-7 mol

2.what is the hydronium ion concentration is a solution having a pH of 0.050 at room temperature?
1. 3.00M
2. 0.951M
3. none of these
4. 2.00 x 10^-13 M
5. 0.891M

3. What is the pH of a solution labeled 0.00013M HNO3?

1. 10.00
2. 11.11
3. 4.11
4. 2.89
5. 3.89

4. What is the pH of an acid solution obtained by mixing 200mL of 0.0155M H2SO4 and 300mL of an 0.210M HCI solution? assume all of the acids dissociate.

1. 1.2
2. 0.460
3. 1.9
4. 0.523
5. 1.16
6. 2.2
7. 0.859

Answer 1

1. pH6 means [H+] of 10-6 mole/liter. You should be able to figure out the rest.
2. pH of 0.05, figure out [H+]
3. Since HNO3 totally ionizes, [H+]=1.3x10-4. So find pH
4. Since H2SO4 produces two ions per dissociated moleule, the amount of H+ is
(1/5)x2x0.0155=0.00602 moles.
Do the same calculation for HCl (1 ion)
Add the H+ and divide by 500 mL to get [H+] from which you calc. pH.

Answer 2

1. 1.8x10^-6
2. 0.891
3. 3.89
4. 0.859