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in case of any doubt.
Question 6: (1 point) Selenous acid, H2SO3, is a diprotic acid with pKa,1 = 2.64 and...
Hydroselenic acid, H2Se, is a diprotic acid with pKa,1 = 3.89 and pKa,2 = 11.01 at 25 °C. For 0.147 mol L−1 H2Se(aq) at 25 °C, calculate: (a) the fraction, α1, of H2Se that exists in the singly-ionized form, HSe− α1 = (Enter a number between 0 and 1, accurate to 2 significant figures.) (b) the equilibrium concentration of the doubly-ionized form, Se2− [Se2− ]eq = mol L−1 (Enter a number accurate to 2 significant figures.) (c)...
For H2SO4, Ka,1 is very large and pKa,2 = 1.96 at 25 °C. For 0.00189 mol L−1 H2SO4(aq) at 25 °C, calculate: (a) the equilibrium concentration of the singly-ionized form, HSO4− (b) the fraction, α2, of H2SO4 that exists in the doubly-ionized form, S (c) the pH
Question 6 (1 point) 1.681 g of an unknown diprotic acid are used to make a 100.00 mL solution. Then 25.00 mL of this solution is transferred to an Erlenmeyer flask and is titrated with 0.1047 M NaOH. The titration endpoint is reached after 0.00411 mol of NaOH is added using the burette. What is the molar mass of the diprotic acid? Provide your answer to the correct number of significant figures. Your Answer: Answer units
1)Which expression is the correct form of the Henderson-Hasselbalch equation? pH = pKa + log([base]/[acid]) pKa = pH + log([base]/[acid]) pH = pKa − log([base]/[acid]) pH = pKa + log([acid]/[base]) 2) Use the Henderson-Hasselbalch equation to calculate the pH of a buffer solution prepared by mixing equal volumes of 0.220 M NaHCO3 and 9.00×10−2 M Na2CO3. (Ka values are given in Appendix C.) Express your answer using three significant figures.
Question 4 (1 point) 0.444 g of an unknown diprotic acid is dissolved in about 60 mL of water in a beaker. The solution is transferred to a 100.00 mL volumetric flask, which is then filled up to the mark. The solution is mixed by inverting multiple times. 25.00 mL of this solution is then transferred to an Erlenmeyer flask for the titration. What mass of the diprotic acid is in the 25.00 mL that is transferred? Provide your answer...
Question 17 (1 point) What is the pH of stomach acid in which [HCl] = 0.151 M? Enter your answer with no units to the correct number of significant figures. Your Answer Answer Save ch
Unknown acid 2 6. Complete the following table. Trial 1 Trial 2 Trial 3 Mass of unknown (8) 0.175 0.120 0.122 Initial buret reading (mL) 0.00 22.37 0.00 Final buret reading (mL) 22.37 44.85 22.83 Volume of NaOH added (mL) 22.37 22.48 22.83 We will assume that the data collected for the first trial is not accurate. 7. What is the average mass of unknown acid for Trials 2 and 3? (Must show calculations) 8. What is the average volume...
Question 27 (1 point) When choosing an acid to make a buffer, choose one whose pKa is closest to the pH of the buffer. True False Question 28 (1 point) In General, metals can act as both lewis acids and arrhenius acids as well. True False False Question 25 (1 point) For reactions at equilibrium, the standard free gibbs energy equal zero. True False Question 26 (1 point) The nuclear binding energy is the energy released when combining multiple nuclei...
Titration: Acids and Bases
2. How can you determine which acid is diprotic?
3. using the answers to questions one and two, which acid is
diprotic?
4. Which base has more hydroxide ions per molecule?
Acid Volume Base Base Initial Volume (mL) Base Final Volume (mL) Volume of Base Used (mL) Acid: Base Ratio Acid 1 20 mL Base 1 50 mL 34.5 15.5 4:3 Acid 2 20 mL Base 1 Acid 1 20 mL Base 2 Acid 2 20...
1) Which substance will raise the pH of the solution when added to an acetic acid solution that has a pH of 4.12? KI NaCHO2 HCl NaC2H3O2 NaBr 2) The solubility product constant for a certain metal chromate, MCrO4 is Ksp = 5.0 × 10−13. What is its solubility in mol/L? Report your answer to TWO significant figures. You may (but are not required to) enter your answer in scientific notation; for example, if your answer is 2.4 × 10−2,...