Sorry I did not post these videos earlier. Our learning objectives for Feb. 9 are:
| –Define and use the Bronsted concept of acids and bases.
–Recognize common acids and bases and write balanced equations for their ionization in water. –Explain what it means to be amphiprotic –Recognize a Bronsted acid or base in a reaction, and identify the conjugate partner of each. –Use the water ionization constant, Kw. –Use the pH concept.
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Before class on Feb. 9
- please watch the following 3 videos (21 min, 21 min, 11 min);
- complete the notes;
- and make a comment.
chemistry matters 
Is every amphiprotic reaction always in equilibrium? Why is this assumed?
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In this video, I learned about acids and bases. Acids can either be defined as proton donors or substances that increase concentration of H+ ions when dissolved in water. Bases can be defined as proton acceptors, or substances that increase OH- concentration when dissolved in water. Amphiprotic substances can be either acids or bases. When an acid loses its proton/ H it forms a conjugate base. When a base gains a proton/H it becomes a conjugate acid. Strong acids dissociate in a very, very forward reaction with a very, very large k value. Their conjugate bases are so weak they are considered negligible. Weak acids only dissociate partially, and have more backwards reaction for their forward reaction. Their conjugate bases are still weak, but not as weak as those of the strong acid conjugate bases. The same logic holds for strong/ weak bases and their conjugate acids. An acid base reaction at equilibrium will favor the direction that gives the stronger base a proton ( it will go in the opposite direction as the side that holds the strong base). Water can auto ionize, and the equilibrium constnant for this is refered to as the ion-product constant for water. At 25 degrees Celsius, it is 1.0 x 10^ -14. pH (potenz-H) is the negative natural log of the concentration of the hydrogen ions. One can also take the “p” of other things such as ion-products constants and OH- concentrations. The pH of a substance will be expressed using two decimal places
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In these videos I learned about conjugate acids and bases as well as pH and how that relates to [H+] andd [OH-].
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In these videos, I learned about bases and acids as well as how to identify them in a reaction and how to use that information to identify the equilibrium shifts. I also learned about pH and how to calculate it as well as how it relates to K. Water can be either an acid or a base. Water can be autoionized and the ion product constant for water is 1.0 x 10^-14.
Question: Can an acid dissociate in a solution other than a water or base solution? Vice versa for a base?
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