Using the data from the table above, which of the following statements best identifies and describes the organism or organisms with the smallest tolerance range to a change in pH in an aquatic environment? The frog and the perch have a critical pH of about 4, indicating that they can tolerate small changes in the acidity of their aquatic environment. The snail has a critical pH of 6, indicating that it can tolerate small changes in the acidity of its aquatic environment. The snail and the clam have a critical pH of 6, indicating that they can tolerate small changes in the acidity of their aquatic environment. The frog has a critical pH of 4, indicating that it can tolerate small changes in the acidity of its aquatic environment.

All of the following statements about the pH scale are true EXCEPT O Cola drinks are very acidic. O The difference in concentration between pH10 and pH 12 is 20. O Neutral is pH 7.00 O Blood is slightly basic. O pH 2 is a strong acid.

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to 2 significant digits, and Each row of the table below describes an aqueous solution at about 25 °C. Complete the table. That is, fill in any missing entries in the second and third columns. Round your entries for your entries for pH to 2 decimal places. solution [10] -7 PH [H₂O] to A 4.2 x 10 B mol/L mol/L ☐ 5 1.22 -10 2.8 x 10 mol/L C ☐

Part A Water ionizes by the equation =H+(aq) + OH (ag) The extent of the reaction is small in pure water and dilute aqueous solutions. This reaction creates the following relationship between [H*] and [OH ]: What is the H† concentration for an aqueous solution with pOH = 2.73 at 25 °C? Express your answer to two significant figures and include the appropriate units. Kw = [H*][OH¯] • View Available Hint(s) Keep in mind that, like all equilibrium constants, the value of Kw changes with temperature. ? [H*] = Value Units

Over the past 250 years, the average upper-ocean pH near the Pacific Northwest has decreased by about 0.1 units, from about 8.2 to 8.1. This drop in pH corresponds to an increase in acidity of about 30%. When CO2 levels in seawater rise, the availability of carbonate ion, CO32−, makes it more difficult for marine organisms to build and maintain shells and other body parts from calcium carbonate. Calculate H3O+ and OH− concentrations at pH levels of 8.2 and 8.1. Demonstrate by calculations that this decrease in pH corresponds to an increase in acidity of about 30%. Explain the relationship between the pH of seawater and the availability of carbonate ions. Does the change in pH from 8.2 to 8.1 result in an increase or decrease in the availability of carbonate ions?

Identify the TRUE statement about acid rain. O Acid rain dissolves marble statues. O Acid rain contains nitric acid and sulfurous acid O Acid rain comes from hydroelectric power plants. O NO combines with oxygen and water to form nitrous acid, which is a component of acid rain. O Acid rain does not corrode steel bridges.

Which of the following is a complete balanced reaction for an Arrhenius base in water? NaOH (s) 2 NaH (s) + O2 (g) →> ○ Mg(OH) 2 (s) → Mg2+ (aq) + OH (aq) ○ HNO2 (aq) → H+ (aq) + NO₂ (aq) KOH (s) →> K+ (aq) + OH¯ (aq)