Ethanol (ethyl alcohol), CH3CH2OH, can act as a BrnstedLowry acid. Write the chemical equation for the reaction of ethanol as an acid with hydroxide ion, OH. Ethanol can also react as a BrnstedLowry base. Write the chemical equation for the reaction of ethanol as a base with hydronium ion, H3O+. Explain how you arrived at these chemical equations. Both of these reactions can also be considered Lewis acid base reactions. Explain this.

Classify each of the following substances as an acid, a base, or a salt. a. HBr b. NaI c. NH4NO3 d. Ba(OH)2

Home gardeners spread aluminum sulfate powder around plants to increase the acidity of the soil. Describe the chemistry at the nanoscale level for such a soil treatment.

Acids You make a solution by dissolving 0.0010 mol of HCl in enough water to make 1.0 L of solution. a Write the chemical equation for the reaction of HCl(aq) and water. b Without performing calculations, give a rough estimate of the pH of the HCl solution. Justify your answer. c Calculate the H3O+ concentration and the pH of the solution. d Is there any concentration of the base OH present in this solution of HCl(aq)? If so, where did it come from? e If you increase the OH concentration of the solution by adding NaOH, does the H3O+ concentration change? If you think it does, explain why this change occurs and whether the H3O+ concentration increases or decreases. f If you were to measure the pH of 10 drops of the original HCl solution, would you expect it to be different from the pH of the entire sample? Explain. g Explain how two different volumes of your original HCl solution can have the same pH yet contain different moles of H3O+. h If 1.0 L of pure water were added to the HCl solution, would this have any impact on the pH? Explain.

For each of the following pairs of acids, indicate whether the first member of the pair is a stronger or weaker acid than the second member of the pair. a. HNO3 and HNO2 b. HF and HBr c. H2CO3 and HClO3 d. HCN and HCl

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.