A solution is made by dissolving 33.5 g of Ba(NO₂)2 in 500.0 mL of water. As NO₂ is a base, write the basic equilibrium equation that exists in solution

A chemist dissolves 815. mg of pure barium hydroxide in enough water to make up 110. mL of solution. Calculate the pH of the solution. (The temperature of the solution is 25 °C.) Be sure your answer has the correct number of significant digits. 0 x10 ×

For each of the following entities • Identify it as a strong or weak acid. • Select the correct arrow to show the changes that occur when the acids are placed in water. • Select the approximate pH for each resulting solution. HCI(aq) is classified as a + acid. The reaction equation with water utilizes which of the following arrows? Choice A Choice B 7 >>7 H2SO3(aq) is classified as a The reaction equation with water would utilize which of the following arrows? Choice A Choice B < 50% H2SO3(aq) + H20(I) • HSO3 (aq) + H30*(aq) The approximate pH of the solution would be

A chemist must prepare 800.0 mL of potassium hydroxide solution with a pH of 12.90 at 25 °C. She will do this in three steps: • Fill a 800.0 mL volumetric flask about halfway with distilled water. Weigh out a small amount of solid potassium hydroxide and add it to the flask. • Fill the flask to the mark with distilled water. Calculate the mass of potassium hydroxide that the chemist must weigh out in the second step. Round your answer to 2 significant digits.

Calculate the pH values of the following solutions. All solutions are prepared in water at 25 oC unless noted otherwise. Kw = 1.0 × 10−14 = [H3O+]×[OH−] at 25 oC. The neutral pH of pure water is 7.00 at 25 °C. If the Kw is 1.47×10−14 at 40 °C, calculate the neutral pH of pure water at 40 °C. A neutral pH means the pH of a solution when [H3O+] = [OH−]

An acid has an initial concentration of 3.87×10−5. The pH of the solution, at equilibrium is 4.41. What is the Ka of the acid.

Enter the formula for the conjugate base of HNO2HNO2. Express your answer as a chemical formula.

Indicate whether the chemical species HC6H5O72- acts as an acid or base when added to water. Please justify your answer with QUANTITATIVE evidence

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

Like other people, I have been able to do more cooking and baking during COVID quarantine and remote teaching and learning. One of the things that I have been learning to make is Irish brown bread, a rather tasty version of a “soda bread.” The bread is called a soda bread because it has baking soda (sodium bicarbonate) in it. Sodium bicarbonate is the conjugate base of carbonic acid. What is the pH of a 0.350 M solution of sodium bicarbonate? (pKa of carbonic acid = 6.35)