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Ch.4 - Chemical Reactions and Chemical Quantities
Tro - Chemistry: A Molecular Approach 5th Edition
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371당신이 사용하는 게 아니라요?교과서 변경
모든 교과서Tro 5th EditionCh.4 - Chemical Reactions and Chemical Quantities문제 31a
4장, 문제 31a

Hydrobromic acid dissolves solid iron according to the reaction:
Fe(s) + 2 HBr(aq) → FeBr2(aq) + H2(g)
What mass of HBr (in g) do you need to dissolve a 3.2-g pure iron bar on a padlock?

검증된 단계별 안내
1
Identify the balanced chemical equation: \( \text{Fe(s)} + 2 \text{HBr(aq)} \rightarrow \text{FeBr}_2\text{(aq)} + \text{H}_2\text{(g)} \).
Determine the molar mass of iron (Fe) and hydrobromic acid (HBr). The molar mass of Fe is approximately 55.85 g/mol, and the molar mass of HBr is approximately 80.91 g/mol.
Calculate the number of moles of iron in the 3.2 g sample using the formula: \( \text{moles of Fe} = \frac{\text{mass of Fe}}{\text{molar mass of Fe}} \).
Use the stoichiometry of the balanced equation to find the moles of HBr needed. According to the equation, 1 mole of Fe reacts with 2 moles of HBr.
Convert the moles of HBr to grams using the formula: \( \text{mass of HBr} = \text{moles of HBr} \times \text{molar mass of HBr} \).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m
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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 balanced equation. It allows us to determine the proportions of substances involved in a reaction. In this case, the stoichiometric coefficients from the balanced equation indicate that 2 moles of HBr are required for every mole of Fe, which is essential for calculating the mass of HBr needed.
추천 영상:
가이드 코스
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 crucial for converting between the mass of a substance and the number of moles. For this problem, knowing the molar mass of HBr (approximately 80.91 g/mol) and Fe (approximately 55.85 g/mol) will help in determining how much HBr is needed to react with the given mass of iron.
추천 영상:
가이드 코스
02:11
Molar Mass Concept

Chemical Reaction Types

Understanding the type of chemical reaction is important for predicting the products and the behavior of reactants. The reaction between iron and hydrobromic acid is a single displacement reaction, where iron displaces hydrogen from HBr. Recognizing this helps in understanding the overall process and the stoichiometric relationships involved in the reaction.
추천 영상:
가이드 코스
02:25
Common Types of Alkane Reactions
관련 실천
교과서 질문

Consider the balanced equation:

SiO2(s) + 3 C(s) → SiC(s) + 2 CO(g)

Complete the table showing the appropriate number of moles of reactants and products. If the number of moles of a reactant is provided, fill in the required amount of the other reactant, as well as the moles of each product that forms. If the number of moles of a product is provided, fill in the required amount of each reactant to make that amount of product, as well as the amount of the other product that forms.

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교과서 질문

Find the limiting reactant for each initial amount of reactants.

2 Na(s) + Br2(g) → 2 NaBr(s)

a. 2 mol Na, 2 mol Br2

b. 1.8 mol Na, 1.4 Br2

c. 2.5 mol Na, 1 mol Br2

d. 12.6 mol Na, 6.9 mol Br2

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교과서 질문

For each of the reactions, calculate the mass (in grams) of the product that forms when 15.39 g of the underlined reactant completely reacts. Assume that there is more than enough of the other reactant.

a. 2 K(s) + Cl2(g) → 2 KCl(s)

b. 2 K(s) + Br2(l) → 2 KBr(s)

c. 4 Cr(s) + 3 O2(g) → 2 Cr2O3(s)

d. 2 Sr(s) + O2(g) → 2 SrO(s)

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교과서 질문

Hydrobromic acid dissolves solid iron according to the reaction:

Fe(s) + 2 HBr(aq) → FeBr2(aq) + H2(g)

What mass of HBr (in g) do you need to dissolve a 3.2-g pure iron bar on a padlock? What mass of H2 would the complete reaction of the iron bar produce?

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교과서 질문

Consider the balanced equation:

SiO2(s) + 3 C(s) → SiC(s) + 2 CO(g)

Complete the table showing the appropriate number of moles of reactants and products. If the number of moles of a reactant is provided, fill in the required amount of the other reactant, as well as the moles of each product that forms. If the number of moles of a product is provided, fill in the required amount of each reactant to make that amount of product, as well as the amount of the other product that forms.

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