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Ch.3 - Chemical Reactions and Reaction Stoichiometry
Brown - Chemistry: The Central Science 14th Edition
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 104

A mixture containing KClO3, K2CO3, KHCO3, and KCl was heated, producing CO2, O2, and H2O gases according to the following equations: 2 KClO31s2¡2 KCl1s2 + 3 O21g2 2 KHCO31s2¡K2O1s2 + H2O1g2 + 2 CO21g2 K2CO31s2¡K2O1s2 + CO21g2 The KCl does not react under the conditions of the reaction. If 100.0 g of the mixture produces 1.80 g of H2O, 13.20 g of CO2, and 4.00 g of O2, what was the composition of the original mixture? (Assume complete decomposition of the mixture.) How many grams of K2CO3 were in the original mixture?

검증된 단계별 안내
1
Identify the chemical reactions involved and the products formed: \(2 \text{KClO}_3 \rightarrow 2 \text{KCl} + 3 \text{O}_2\), \(2 \text{KHCO}_3 \rightarrow \text{K}_2\text{O} + \text{H}_2\text{O} + 2 \text{CO}_2\), \(\text{K}_2\text{CO}_3 \rightarrow \text{K}_2\text{O} + \text{CO}_2\).
Calculate the moles of each gas produced using their respective molar masses: \(\text{H}_2\text{O}\), \(\text{CO}_2\), and \(\text{O}_2\).
Use stoichiometry to determine the moles of each reactant that decomposed to produce the given moles of gases.
Convert the moles of each reactant back to grams using their molar masses to find the mass of each component in the original mixture.
Subtract the masses of \(\text{KClO}_3\), \(\text{KHCO}_3\), and \(\text{K}_2\text{CO}_3\) from the total mass of the mixture to find the mass of \(\text{KCl}\).

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이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
7m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Stoichiometry

Stoichiometry is the calculation of reactants and products in chemical reactions based on the conservation of mass. It involves using balanced chemical equations to determine the relationships between the amounts of substances consumed and produced. In this question, stoichiometry is essential for relating the masses of the gases produced to the amounts of the original compounds in the mixture.
추천 영상:
가이드 코스
01:16
Stoichiometry Concept

Gas Laws

Gas laws describe the behavior of gases in relation to pressure, volume, temperature, and the number of moles. Understanding these laws helps in calculating the expected volumes or masses of gases produced in a reaction. In this scenario, the production of gases like CO2, O2, and H2O must be analyzed to determine the original composition of the solid mixture.
추천 영상:
가이드 코스
01:43
Combined Gas Law

Decomposition Reactions

Decomposition reactions involve the breakdown of a compound into simpler substances, often producing gases. In this question, the decomposition of KClO3, KHCO3, and K2CO3 is crucial to understanding how the original mixture generates the observed gases. Recognizing the specific products formed from each compound allows for the calculation of their initial amounts in the mixture.
추천 영상:
가이드 코스
01:30
Alcohol Reactions: Dehydration Reactions