1. Consider Lewis structure for methane (CH4). a. If methane were to behave as an acid (if possible), draw the Lewis structure of its resulting conjugate base. b. Reflecting on your answer for Part A and using the three acid-base models above, would you predict the conjugate base would form? (Does this situtation make sense)? c. If methane were to behave as a base (if possible), draw the Lewis structure of its resulting conjugate acid. d. Reflecting on your answer for Part A and using the three acid-base models above, would you predict the conjugate acid would form? (Does this situtation make sense)?

a. The formula for the conjugate base of HSO3 is T b. The formula for the conjugate acid of H₂PO4 is

Ammonia is a weak base and acetic acid is a weak acid. Which statement is true of a solution of ammonium acetate?     a. It is weakly acidic.   b. It is weakly basic.   c. It is strongly acidic.   d. It is neutral.   e. We cannot predict its acid-base properties without more information.

Order these chemical species by increasing pH of an 0.1 M aqueous solution of each. That is, imagine making an 0.1 M solution of each species. Select 1 next to the species that makes the solution with the lowest pH. Select 2 next to the species that makes the solution with the next higher pH, and so on. Notice that some of the rankings have been filled in for you already. Also notice that water is on the list. For that particular case, just compare the pH of pure water to the pH of the other solutions. Note for advanced students: for all charged species, you may assume the necessary counterions act as neither acids nor bases. species ΙΟ HF HIO F ОН NO₂ HNO₂ H₂O relative pH of 0.1 M aqueous solution (Choose one) (Choose one) 3 5 8 (highest) (Choose one) 2 (Choose one) X Ś

Order these chemical species by increasing pH of an 0.1 M aqueous solution of each. That is, imagine making an 0.1 M solution of each species. Select 1 next to the species that makes the solution with the lowest pH. Select 2 next to the species that makes the solution with the next higher pH, and so on. Notice that some of the rankings have been filled in for you already. Also notice that water is on the list. For that particular case, just compare the pH of pure water to the pH of the other solutions. Note for advanced students: for all charged species, you may assume the necessary counterions act as neither acids nor bases. species relative pH of 0.1 M aqueous solution + C6H5NH3 HCOOH 3 2 HCOO (Choose one) H₂O HONH3 5 + (Choose one) C6H5NH2 (Choose one) H₂O+ (Choose one) HONH2 8 (highest)

Order these chemical species by increasing pH of an 0.1 M aqueous solution of each. That is, imagine making an 0.1 M solution of each species. Select 1 next to the species that makes the solution with the lowest pH. Select 2 next to the species that makes the solution with the next higher pH, and so on. Notice that some of the rankings have been filled in for you already. Also notice that water is on the list. For that particular case, just compare the pH of pure water to the pH of the other solutions. Note for advanced students: for all charged species, you may assume the necessary counterions act as neither acids nor bases. relative pH of 0.1 M aqueous solution species ? 103 |(Choose one) ▼ OH |(Choose one) ▼ H,0 4 HC,04 6. HIO, 1 (lowest) NO2 |(Choose one)

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Order these chemical species by increasing pH of an 0.1 M aqueous solution of each. That is, imagine making an 0.1 M solution of each species. Select 1 next to the species that makes the solution with the lowest pH. Select 2 next to the species that makes the solution with the next higher pH, and so on. Notice that some of the rankings have been filled in for you already. Also notice that water is on the list. For that particular case, just compare the pH of pure water to the pH of the other solutions. Note for advanced students: for all charged species, you may assume the necessary counterions act as neither acids nor bases. relative pH of species 0.1 M aqueous solution HC₂04 7 + H₂O* 1 (lowest) H₂PO4 (Choose one) H₂PO4 4 103 (Choose one) HIO₂ H₂C₂O4 (Choose one) H₂O (Choose one)

Given: HCHO_2(aq) + H_2O = CHO_2- (aq) + H_3O+ a. What is the conjugate of HCHO_2(aq)? b. Between these two species HCHO_2(aq) and its conjugate, what is the conjugate acid? c. What is the conjugate base?

What is the best rationale for the difference in acidity in a 2,2-difluoro isomer and a 3,3-difluoro isomer. A. The more acidic compound has a hydrogen attached to a more electronegative atom B.The more acidic compound has a hydrogen attached to a larger atomic radius atom C. The more acidic compound has a more stable conjugate base because of addition resonance structures stabilizing the charge D. The more acidic compound has a stronger molecular dipole that increases the polarization of the acidic hydrogen E. The more acidic compound has a greater amount of s-character in the acidic bond.