1) Write an equation for the proton-transfer reaction between a phosphate ion (PO43-) and water, and determine in which direction the equilibrium is favored? By knowing the relative acid and base strengths of the species involved in the reaction, you will be able to predict the direction in which the equilibrium is favored

1) Write an equation for the proton-transfer reaction between a phosphate ion (PO₄^3-) and water, and determine in which direction the equilibrium is favored? By knowing the relative acid and base strengths of the species involved in the reaction, you will be able to predict the direction in which the equilibrium is favored.

2. Milk has an H₃0⁺ concentration of 4.5 x 10^-7 M. What is the value of [OH^-]? Is milk acidic, neutral, or basic? The OH^- concentration can be found by dividing K_w by [H₃0⁺]. An acidic solution has [H₃0⁺] > 10^-7 M, a neutral solution has [H₃0⁺] =10^-7 M, and a basic solution has [H₃0⁺] < 10^-7 M.

3. A cleaning solution is found to have [OH^-] of 1 x 10^-3 M. What pH is this? To find pH, we must first find the value of [H₃0⁺] by using the equation [H₃0⁺] = K_w/[OH^-]. Alternatively, we can calculate pOH of the solution and then use the logarithmic form of the K_w equation: pH + pOH = 14.00

4. Soft drinks usually have a pH of approximately 3.1. What is the [H₃0⁺] concentration in a soft drink? To convert from a pH value to an [H₃0⁺] concentration requires using the equation [H₃0⁺] = 10^-pH, which requires finding an antilogarithm on a calculator.

5. What is the pH of a 0.0032 M solution of NaOH? Because NaOH is a strong base, the OH^- concentration is the same as the NaOH concentration. Starting with the OH^- concentration, finding pH requires either using the K_w equation to find [H₃0⁺] or calculating pOH and then using the logarithmic form of the K_w equation.

CHE*220, Assignment 1

1. Ivanka brings a 750 ml cup of coffee to class, if she drinks the cup of coffee how many moles of hydrogen has she consumed? (Assume the pH of the coffee is 5.)

2. How many hydrogen ions has she consumed?

3. Instead Rudy consumes 500 ml of orange juice (pH 3.3), who has consumed more hydrogen ions?