Delivery-1-FCL22 - Acid base, molecules organic names. Chemistry 1 and 2 from UPC PDF

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Acid base, molecules organic names. Chemistry 1 and 2 from UPC...

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I- Acid Base 1. Give industrial examples of chemical applications Chemistry is used in a huge range of activities in the industrial environment, it can be used for instance in agriculture or industrial processes in things related to the human body. Moreover, we can think of the sulfuric acid that can be used as a fertilizer or to make explosives or ammonia which can be used in paper production. Calcium hydroxide can be used in wastewater treatment, what is its role? Explain it briefly What are the main applications of "soda"? One of the most common alkalis used to provide alkalinity in wastewater treatment is caustic soda. It has properties which provide alkalinity and pH control to wastewater treatment systems. The main applications of soda are Glass Manufacture, Detergent Manufacture. It can also be used to remove stains, alcohol, and grease on clothes or as a fertilizers. 2. Write examples of acids in equilibrium (at least 3) and mark who is the acidic species and who is the basic species. What name do these two species receive if they are in the same balance? Why? -

HCN⇌H+ + CNNH4⇌NH3 + H+ HA⇌H+ + A-

In red we have the acidic species and in green the basic species If the two species are in the same balance they are called amphoteric, because it can be used as a base or as an acid. IMPORTANT: to work correctly with the logarithmic diagrams, we will always write the equilibria with the acidic species on the left, as a reactant. Chemically, this reaction makes as much sense as the reverse. In the specific case of a strong base, the base species is placed to the left, since there is no equilibrium. 3. Write 5 strong acids, 5 strong bases and their corresponding dissociations. Write 5 weak acids, 2 weak bases and their corresponding dissociations Where appropriate, write the equilibrium constant and the pKa.

4. How is pH defined? What are the characteristics of a neutral solution? pH is defined by minus logarithm of the concentration of H+ in the equilibrium, it goes from 1 to 14 in a scale and it is used to determine the acidity or the basicity of the solution. For a neutral solution the characteristics are that the pH equals to 7 and we have [H+]=[HO-] 5. In logarithmic (DL) diagrams, what is plotted against what? In the logarithmic (DL) diagrams we have the pH (in the horizontal abcise) plotted against the logarithmic concentration (in the vertical abcise) 6. In a "non specific" acid, HA, what does A mean? Does it have a charge? We use A to refer to a general anion. It has a negative charge. 7. Capture the screenshots from minute 9.40 and explain: What could be the problem statement? Write it Indicates the meaning of the diagonal of the first quadrant (solid black), the perpendicular (dashed black), red line, blue line, green line dotted, yellow line.

The problem statement could be to find the pH of the solution and of each species. -The diagonal of the first quadrant, (solid black), represents the logarithmic concentration of OH. -The perpendicular to the diagonal of the first quadrant, (dashed black), represents the logarithmic concentration of H. -The red line represents the logarithmic concentration of the acid -The blue line represents the logarithmic concentration of the base -The green line represents is a perpendicular line at the pH equal to the pKa -The yellow line represents the pH of the base specie 8. Capture the screen at minute 10:29, write the problem statement and explain again the meaning of each of the lines

-The diagonal of the first quadrant, (solid black), represents the logarithmic concentration of OH. -The perpendicular to the diagonal of the first quadrant, (dashed black), represents the logarithmic concentration of H. -The red line represents the logarithmic concentration of the acid -The blue line represents the logarithmic concentration of the base

-The green line represents is a perpendicular line at the pH equal to the pKa -The yellow line represents the pH of the acid specie 9. With what you have learned in these two sections, draw the logarithmic diagram with the meaning of each of the lines, of an acid (HA) with a pKa = 5.7 and it is assumed an initial concentration of 0.1 M. Use colors to say the meaning of each of the lines. Calculate, graphically, the pH of that solution. Do initially by hand, and later, take the Excel from de Atenea.

10. What does A mean in H2A? Does it have charge? A is an anion and it has 2 negative charges in this case.

11. Draw the DL corresponding to carbonic acid with a concentration of 0.1 M (you will have to look for the constants in the corresponding tables). Graphically indicates the pH of each of the following products: (1) carbonic acid, (2) sodium hydrogen carbonate, (3) sodium carbonate. Explains (Based on the explanations of the video) how affected the pH in each of the cases if the concentration decreases to 0.01 M. Justify it graphically. You can use Excel with the DL that you have hanging in Atenea.

How affected the pH is in each of the cases if the concentration decreases to 0.01 M? - When the base concentration decreases to 0,01M the pH decreases - When the acid concentration decreases to 0,01M the pH increases - When the amphoteric concentration decreases to 0,01M, the pH stays the same....