Skip to main content
Ch.3 - Chemical Reactions and Reaction Stoichiometry
Chapter 3, Problem 62b

The reaction between potassium superoxide, KO2, and CO2, 4 KO2 + 2 CO2¡2K2CO3 + 3 O2 is used as a source of O2 and absorber of CO2 in selfcontained breathing equipment used by rescue workers. (b) How many grams of KO2 are needed to form 7.50 g of O2?

Verified step by step guidance
1
Identify the balanced chemical equation: \(4 \text{ KO}_2 + 2 \text{ CO}_2 \rightarrow 2 \text{ K}_2\text{CO}_3 + 3 \text{ O}_2\).
Determine the molar mass of \(\text{O}_2\) and \(\text{KO}_2\) using the periodic table.
Calculate the moles of \(\text{O}_2\) produced from 7.50 g using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\).
Use the stoichiometry of the balanced equation to find the moles of \(\text{KO}_2\) needed. According to the equation, 4 moles of \(\text{KO}_2\) produce 3 moles of \(\text{O}_2\).
Convert the moles of \(\text{KO}_2\) to grams using its molar mass: \(\text{mass} = \text{moles} \times \text{molar mass}\).

Verified Solution

Video duration:
1m
This video solution was recommended by our tutors as helpful for the problem above.
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 relationships between the amounts of substances consumed and produced. In this case, it helps us find the mass of KO2 needed to produce a specific mass of O2 by using the mole ratios from the balanced equation.
Recommended video:
Guided course
01:16
Stoichiometry Concept

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is essential for converting between the mass of a substance and the number of moles. For KO2 and O2, knowing their molar masses allows us to calculate how many grams of KO2 are required to yield the desired grams of O2.
Recommended video:
Guided course
02:11
Molar Mass Concept

Balanced Chemical Equation

A balanced chemical equation represents a chemical reaction with equal numbers of each type of atom on both sides of the equation. It provides the stoichiometric coefficients that indicate the proportions of reactants and products. Understanding the balanced equation for the reaction between KO2 and CO2 is crucial for determining the quantities of each substance involved in the reaction.
Recommended video:
Guided course
01:32
Balancing Chemical Equations
Related Practice
Textbook Question

Epsom salts, a strong laxative used in veterinary medicine, is a hydrate, which means that a certain number of water molecules are included in the solid structure. The formula for Epsom salts can be written as MgSO4 # xH2O, where x indicates the number of moles of H2O per mole of MgSO4. When 5.061 g of this hydrate is heated to 250 C, all the water of hydration is lost, leaving 2.472 g of MgSO4. What is the value of x?

1350
views
Textbook Question

Hydrofluoric acid, HF(aq), cannot be stored in glass bottles because compounds called silicates in the glass are attacked by the HF(aq). Sodium silicate (Na2SiO3), for example, reacts as follows: Na2SiO3(s) + 8 HF(aq) → H2SiF6(aq) + 2 NaF(aq) + 3 H2O(l) (a) How many moles of HF are needed to react with 0.300 mol of Na2SiO3? (b) How many grams of NaF form when 0.500 mol of HF reacts with excess Na2SiO3? (c) How many grams of Na2SiO3 can react with 0.800 g of HF?

5329
views
Textbook Question

The reaction between potassium superoxide, KO2, and CO2, 4 KO2 + 2 CO2¡2K2CO3 + 3 O2 is used as a source of O2 and absorber of CO2 in selfcontained breathing equipment used by rescue workers. (a) How many moles of O2 are produced when 0.400 mol of KO2 reacts in this fashion?

1945
views
Textbook Question

Several brands of antacids use Al1OH23 to react with stomach acid, which contains primarily HCl: Al(OH)3(s) + HCl(aq) → AlCl3(aq) + H2O(l) (b) Calculate the number of grams of HCl that can react with 0.500 g of Al(OH)3. (c) Calculate the number of grams of AlCl3 and the number of grams of H2O formed when 0.500 g of Al(OH)3 reacts.

607
views
Textbook Question

An iron ore sample contains Fe2O3 together with other substances. Reaction of the ore with CO produces iron metal: Fe2O3(s) + CO(g) → Fe(s) + CO2(g) (b) Calculate the number of grams of CO that can react with 0.350 kg of Fe2O3. (c) Calculate the number of grams of Fe and the number of grams of CO2 formed when 0.350 kg of Fe2O3 reacts.

1331
views
Textbook Question

Aluminum sulfide reacts with water to form aluminum hydroxide and hydrogen sulfide. (a) Write the balanced chemical equation for this reaction. (b) How many grams of aluminum hydroxide are obtained from 14.2 g of aluminum sulfide?

2481
views