Purine Solution Chemistry Concepts

The video tutorial explains how to determine the base dissociation constant (KB) of a 0.1 molar purine solution with a pH of 9.09. It begins by setting up the chemical equation for purine in water, where purine accepts a proton to form a cation and hydroxide ion. The tutorial then calculates the hydroxide ion concentration using the pH value and sets up an IC table to find equilibrium concentrations. Finally, it uses these concentrations to calculate the KB value, demonstrating the process step-by-step.

What is the initial concentration of the purine solution given in the problem?

• 10 molar

• 0.1 molar

• 1 molar

• 0.01 molar

What is the pH of the purine solution?

• 4.91

• 14.00

• 9.09

• 7.00

How do you calculate the pOH from the given pH?

• pOH = 14 + pH

• pOH = pH - 14

• pOH = pH + 14

• pOH = 14 - pH

What is the hydroxide ion concentration when the pOH is 4.91?

• 1.23 * 10^-6 M

• 1.23 * 10^-4 M

• 1.23 * 10^5 M

• 1.23 * 10^-5 M

What does the 'I' in the ICE table stand for?

• Initial

• Inert

• Intermediate

• Ion

What is the change in purine concentration represented by in the ICE table?

• X

• Y

• Z

• W

What is the equilibrium expression for Kb?

• Kb = [cation][purine] / [hydroxide ion]

• Kb = [purine][hydroxide ion] / [cation]

• Kb = [cation][hydroxide ion] / [purine]

• Kb = [hydroxide ion][purine] / [cation]

What is the equilibrium concentration of the cation in the solution?

• 1.23 * 10^-5 M

• 1.23 * 10^-4 M

• 1.23 * 10^5 M

• 1.23 * 10^-6 M

What is the final calculated value of Kb?

• 1.51 * 10^-9

• 1.51 * 10^9

• 1.51 * 10^5

• 1.51 * 10^-5

Which ion is produced when purine accepts a proton from water?

• Hydronium ion

• Hydroxide ion

• Sodium ion

• Chloride ion