A chemist must prepare 500.0mL of hydrochloric acid solution with a pH of 0.90 at 25°C. He will do this in three steps:   Fill a 500.0mL volumetric flask about halfway with distilled water.   Measure out a small volume of concentrated (7.0M) stock hydrochloric acid solution and add it to the flask.   Fill the flask to the mark with distilled water. Calculate the volume of concentrated hydrochloric acid that the chemist must measure out in the second step. Round your answer to 2 significant digits.    [] mL

A chemist titrates 210.0 mL of a 0.7303M potassium hydroxide (KOH) solution with 0.0877M HNO3 solution at 25 °C. Calculate the pH at equivalence. Round your answer to 2 decimal places. Note for advanced students: you may assume the total volume of the solution equals the initial volume plus the volume of HNO3 solution added. pH = X

A chemist dissolves 891. mg of pure hydrochloric acid in enough water to make up 270. mL of solution. Calculate the pH of the solution. Round your answer to 3 significant decimal places. ☐ ☐ x10

pH: 3 [H*]: 10-3 M [OH]: 10-11 M 14 1 1 7 · 10-7 10-7 10-14 10-14 Dip litmus paper into the solution or add a drop of universal indicator. Use the sliders to change the pH of the solution and observe the effect on the indicators. Click Reset to start over. Help Reset The solution turns orange when the univeral indicator is added to it. Is the solution basic, acidic, or neutral?

A chemist must prepare 700.0 mL of sodium hydroxide solution with a pH of 12.30 at 25 °C. She will do this in three steps: • Fill a 700.0 mL volumetric flask about halfway with distilled water. • Weigh out a small amount of solid sodium hydroxide and add it to the flask. • Fill the flask to the mark with distilled water. Calculate the mass of sodium hydroxide that the chemist must weigh out in the second step. Round your answer to 2 significant digits. Ox10

For a 0.00533 M solution of sodium benzoate, NaC6H5CO2, do the following. Identify the major species (other than water) that has no effect on pH. Include charges and physical states in your answer. eTextbook and Media Balance the equilibrium reaction for the major species that does have an effect on pH. Include charges and physical states in your answer. +H,0(1)= Compute the pH of the solution. Ką of HC6H5CO2 is 6.3E-5. i

A chemist dissolves 759. mg of pure hydrochloric acid in enough water to make up 80. mL of solution. Calculate the pH of the solution. Round your answer to 2 significant decimal places.

Will 260.0 milligrams of calcium carbonate raise the pH of 75.0 milliliters of stomach fluid from a low pH of 1.00 into the normal pH range of 1.50-3.50? In the last discussion, you calculated that 260.0mg of calcium carbonate is 0.2600g of calcium carbonate. The next step is to figure out the formula of calcium carbonate and to calculate the molar mass of calcium carbonate in grams per mole. Submit a reply that that tells how you decided to approach the problem and shows the work that results in an answer. Use correct units and significant figures and correct symbols for elements and math. In addition, select another student's explanation that makes sense to you and reply with a comment about the insight you gained from their answer. Calcium carbonate is an ionic compound. Ionic nomenclature is in section 2.8. Molar mass is described on page 74 in section 2.8 of the textbook.

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When 46.5 ml of 0.100 M Ba(OH)2 is mixed with 290.7 ml of 0.200 M HCI, the reaction goes to completion. Calculate the pH of the solution. Do not include units in your answer, If you round during your calculations make sure to keep at least 3 decimal places. Report your answer to two (2) decimal places. Possibly helpful equations: pH = -log(H'] [H*]= 10- pH Kw =[H*] [OH ] Kw = 1.0 x 10-14 Answer: