Skip to main content
Ch.16 - Aqueous Equilibria: Acids & Bases
Chapter 16, Problem 155a

During a certain time period, 4.0 million tons of SO2 were released into the atmosphere and subsequently oxidized to SO3. As explained in the Inquiry, the acid rain produced when the SO3 dissolves in water can damage marble statues: CaCO3(s) + H2SO4(aq) → CaSO4(aq) + CO2(g) + H2O(l) (a) How many 500 pound marble statues could be damaged by the acid rain? (Assume that the statues are pure CaCO3 and that a statue is damaged when 3.0% of its mass is dissolved.)

Verified step by step guidance
1
Convert the mass of SO_2 released (4.0 million tons) to grams. Note that 1 ton = 2000 pounds and 1 pound = 453.592 grams.
Calculate the moles of SO_2 using its molar mass (64.07 g/mol).
Assume complete conversion of SO_2 to SO_3 and then to H_2SO_4. Use the stoichiometry of the reaction to find the moles of H_2SO_4 produced.
Determine the mass of CaCO_3 that can react with the produced H_2SO_4 using the stoichiometry of the reaction: CaCO_3(s) + H_2SO_4(aq) → CaSO_4(aq) + CO_2(g) + H_2O(l).
Calculate the number of 500-pound marble statues that could be damaged, knowing that 3.0% of each statue's mass is dissolved.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
8m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Stoichiometry

Stoichiometry is the calculation of reactants and products in chemical reactions based on the balanced chemical equation. It allows us to determine the amount of substances consumed and produced in a reaction, which is essential for solving problems involving mass and moles. In this question, stoichiometry will help calculate how much CaCO3 can be dissolved by the acid rain produced from the oxidation of SO2.
Recommended video:
Guided course
01:16
Stoichiometry Concept

Acid-Base Reactions

Acid-base reactions involve the transfer of protons (H+) between reactants, leading to the formation of water and salts. In this context, sulfuric acid (H2SO4) reacts with calcium carbonate (CaCO3) to produce calcium sulfate (CaSO4), carbon dioxide (CO2), and water (H2O). Understanding this reaction is crucial for determining how the acid rain affects marble statues, which are primarily composed of CaCO3.
Recommended video:
Guided course
01:09
Acid-Base Reaction

Mass Percent and Dissolution

Mass percent is a way to express the concentration of a substance in a mixture, calculated as the mass of the solute divided by the total mass of the solution, multiplied by 100. In this problem, knowing that 3.0% of the marble statue's mass is dissolved helps to quantify the amount of CaCO3 that can be affected by the acid rain. This concept is key to determining how many statues can be damaged based on the total amount of acid produced.
Recommended video:
Guided course
00:38
Mass Percent Calculation