Name: ____________________________ Block: _______ Date: _____________________________ Online Acid/Base practice: 1. What is the pH of 0.25L of chicken soup? How about 0.5L? Is it acidic or basic? pH = 5.8 for 0.25L and 0.5L acidic 2. Does the pH change if you have a greater volume of the substance? No 3. What happens to the pH of the soup if you start with 0.25L and add 0.75L of water? What value is the pH now? Is it acidic or basic? It increases. About 6.3 acidic 4. What is the pH of 0.05L of hand soap? Is it acidic or basic? pH = 10 basic 5. What happens to the pH if you add about 0.5L of water? What is the new value? pH decreases pH = about 8.9 6. What is the pH of 0.2L of blood? Is it acidic or basic? pH= 7.4 slightly basic 7. What happens to the pH if you add 0.4L of water to the blood? What is the new pH value? It decreases pH= 7.15 8. What happens to the pH if you then add 0.6L of blood to the mixture? Is the mixture acidic or basic? Was the pH the same as it was in #6? It increases slightly basic pH= about 7.3 no, it is lower. 9. Let’s say that I want to get my mixture to a certain pH but I add too much water to my solution. Can I just add the same volume of my substance as the water I added back into the mixture to get my initial pH? Why/ why not? No, because if you add the same amount of substance your pH will be lower/higher than it initially was. (Equilibrium has been shifted too far in one direction) 10. I want to have orange juice with my breakfast but my teeth are very sensitive to acidic drinks. What is the pH of orange juice? Is it acidic or basic? pH = 3.5L acidic 11. I’ve decided that I still want to have some orange juice. In order to make it less acidic, I need to raise the pH 0.5 units higher. How much water do I need to add to dilute my juice to this level? About 0.55 L 12. Most of the things that we can drink (safely) on this list are acidic / basic (circle one). 13. If I have 0.35L of soda (12 fluid ounces), what is the pH? Is soda acidic or basic? How much water do I need to add to increase the pH to 3? About 0.76L 13. As you probably know, a dentist will tell you that soda is bad for your teeth. What other item on this list is soda’s pH closest to? Is it acidic or basic? Knowing this information, why do you suppose soda (even diet) is bad for your teeth? It is closest to vomit (stomach acid) it is acidic It is bad for you because it is almost as acidic as stomach acid, which eats away at items you eat to prepare for digestion. It can eat away at your tooth enamel. 14. An acid is called an acid because of the amount of positive hydrogen ions that are dissolved in the solution. Based on this concept, which substance has more hydrogen ions dissolved in the solution? (circle one for each) a. Vomit or chicken soup b. Hand soap or drain cleaner c. Blood or soda 15. A base is called a base because of the amount of hydroxide ions that are dissolved in the solution. Based on this concept, which substance has more hydroxide ions dissolved in the solution? (circle one for each) a. Milk or spit b. Blood or coffee c. soda pop or battery acid