Hydrazine, N2H4 (having the structure H2NNH2), and its derivatives have been used as rocket fuels. Draw the Lewis electron-dot formula for the hydrazine molecule. Describe the geometries expected about the nitrogen atoms in this molecule. Why would you expect hydrazine to be basic? Which substance, NH3 or N2H4, would you expect to be more basic? Why? Write the chemical equation in which hydrazine reacts with hydrochloric acids to form the salt N2H5Cl. Consider the positive ion of this salt. How does its basic character compare with that of NH3 and N2H4? Explain.

10. Calculate the pH of a 1.6 M solution of aniline salt (K, (aniline) = 4.3 x 1010). -N: H H Aniline Salt Aniline

7. Carbonic acid (H2CO3) is a diprotic acid with Ka1 = 4.30 × 10–7 and   Ka2 = 5.60 × 10–11 What is the pH in a 1.834 M solution of carbonic acid? 8.  The ionization constant, Kb, for weak base, B, is 7.56 × 10–5.  What is the pH of a 0.6545 M solution of this base? The equation for the ionization of weak base B as follows.            B (aq) + H2O(l) ⇌ BH+(aq) + OH⁻(aq)

Over the past 250 years, the average upper-ocean pH near the Pacific Northwest has decreased by about 0.1 units, from about 8.2 to 8.1. This drop in pH corresponds to an increase in acidity of about 30%. When CO2 levels in seawater rise, the availability of carbonate ion, CO32−,  This makes it more difficult for marine organisms to build and maintain shells and  other body parts from calcium carbonate. Calculate H3O+ and OH− concentrations at pH levels of 8.2 and 8.1. Demonstrate by calculations that this decrease in pH corresponds to an increase in acidity of about 30%. Explain the relationship between the pH of seawater and the availability of carbonate ion. Does the change in pH from 8.2 to 8.1 result in an increase or decrease in the availability            of carbonate ion?

Decide whether each of the following substances should be classified as a Lewis acid or a Lewis base. a. BC13 (Hint: Draw the electron dot structure.) O Lewis acid OLewis base b. C2H4 (NH2 )2, ethylenediamine (Hint: Draw the electron dot structure.) OLewis acid OLewis base c. The reactants in the reaction Fe* (aq) + 6 H2O(t)2 Fe(H2O)e + (aq) Lewis acid: Lewis base: Drag and drop your selection from the following list to complete the answer: Fe* (aq) H2 O(4) 3+

1.Carbon occurs in water in 3 different photons, CO2, HCO3', and CO3 2. a- Is there a certain pH value at which carbon occurs in all 3 forms? Yes/NO b- In seawater (pH =8.2) the greatest percentage of carbon occurs in the form HCO3? Yes/NO 2.Carbon can occur in Water in three different fotons (substance) as Carbon dioxide (CO2), hydrogen carbonate (HCO3), or Carbonate ( The pH value of (water indicates how high the percentage of three forms is (substance amount). The diagram shows these substances amount depending on the pH value. 100 80 Hideogen Carbonate 60 Carbon dioxide Carbonate (Co) 20 PH value 10 11 12 13 Which of the following is correct A)ln Seawater (pH value of 8.2) The greatest percentage of carbon occurs in the form of HCO3 B) There is a pH value at which carbon occurs in water in the form of CO, as in the form of HCO3 and CO3 2 a. Only A is correct b. Only B is correct c. Both are correct d. None is correctn dl

What is the pH of a 0.24 M solution of sodium propionate, NaC3H5O2, (base) at 25°C? (For propionic acid, HC3H5O2, Ka 1.3 x 10-5 at 25°C.) O 4.87 O 6.34 O 7.66 9.13 O 11.10

The active ingredient in aspirin is acetylsalicylic acid ( HC,H704), a monoprotic acid with a K, of 3.3 x 104 at 25 °C. Item 13 Part A A solution of sodium acetate (NaCH3CO0) has a pH of 9.72. The acid-dissociation constant for acetic acid is 1.8 x 10 5. What is the molarity of the solution? Express your answer to two significant figures and include the appropriate units. ? molarity = Value Units

26.What would be the pH of a solution of hypobromous acid (HOBr) prepared by dissolving9.7 grams of the acid in 20 mL of pure water (H2O)? The Ka of hypobromous acid is2 × 10−91. 12. 43. 104. 135. 6