The reaction 2 H_2 O_2(aq) right arrow 2 H_2 O(I) + O_2 (g) is first order…

The reaction 2 H_2 O_2(aq) right arrow 2 H_2 O(I) + O_2 (g) is first order in H_2 O_2 and has a rate constant of 0.00790 s^-1 at 20 degree C. A reaction vassel initially contains 159 mL of 26% H_2 O_2 by mass solution (the density of the solution is 1.17 g/mL). The gaseous oxygen is collected over water at 20 degree C as it forms. What volume of O_2 forms in 86 seconds at a barometric pressure of 746.5 mmHg? (the vapor pressure of water at this temperature is 17.5 mmHg). Determine the mass of Ca(OH)_2 in 365 mL of an aqueous solution that has a pH of 12.04.