/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 125 Iron forms a sulfide with the ap... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Iron forms a sulfide with the approximate formula \(\mathrm{Fe}_{7} \mathrm{~S}_{8}\). Assume that the oxidation state of sulfur is \(-2\), and that iron atoms exist in both \(+2\) and \(+3\) oxidation states. What is the ratio of \(\mathrm{Fe}(\mathrm{II})\) atoms to \(\mathrm{Fe}(\mathrm{III})\) atoms in this compound?

Short Answer

Expert verified
The ratio of \(\text{Fe}^{2+}\) to \(\text{Fe}^{3+}\) atoms is \(\frac{5}{2}\).

Step by step solution

01

Identify the total charge from sulfur atoms

We start by recognizing that the sulfur in the formula has an oxidation state of \(-2\). With \(8\) sulfur atoms, the total negative charge contributed by sulfur is \(-2 \times 8 = -16\).
02

Determine the total positive charge from iron atoms

For the compound to be neutral, the total positive charge from the iron atoms must balance the total negative charge from sulfur. Thus, the total positive charge from iron must be \(+16\).
03

Establish the equations for the oxidation states of iron

Let \(x\) represent the number of \(\text{Fe}^{2+}\) atoms and \(y\) represent the number of \(\text{Fe}^{3+}\) atoms. The charge equation can be written as: \(2x + 3y = 16\). Moreover, since the total number of iron atoms is \(7\) from the compound \(\text{Fe}_7\text{S}_8\), we also have: \(x + y = 7\).
04

Solve the system of equations

We solve the system of equations \(x + y = 7\) and \(2x + 3y = 16\) simultaneously. We can substitute \(x\) from the first equation into the second, giving:\(2(7 - y) + 3y = 16\).Simplifying, we get:\(14 - 2y + 3y = 16\), which simplifies to \(y = 2\).Now we substitute back to find \(x\):\(x + 2 = 7\), thus \(x = 5\).
05

Calculate the ratio of \(\text{Fe}^{2+}\) to \(\text{Fe}^{3+}\)

With \(x = 5\) for \(\text{Fe}^{2+}\) atoms and \(y = 2\) for \(\text{Fe}^{3+}\) atoms, the ratio of \(\text{Fe}^{2+}\) to \(\text{Fe}^{3+}\) is \(\frac{5}{2}\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Fe(II) and Fe(III) ratio
Understanding the ratio of \( \text{Fe}^{2+} \) (or Fe(II)) to \( \text{Fe}^{3+} \) (or Fe(III)) atoms in a compound is crucial for grasping the composition of iron sulfide, specifically \( \text{Fe}_7\text{S}_8 \). Given iron can exist in multiple oxidation states, distinguishing between Fe(II) and Fe(III) helps us determine how they contribute to the overall charge and balance of a compound. In the scenario of \( \text{Fe}_7\text{S}_8 \), we started by assuming that the compound must be neutral overall. This neutrality implies that the total positive charge due to the iron atoms must equal the total negative charge from the sulfur atoms. By setting up equations for both total charge and total atoms, we identified that there are 5 Fe(II) and 2 Fe(III) atoms. Therefore, the ratio is \( \frac{5}{2} \), meaning there are more Fe(II) atoms than Fe(III) in this specific compound.
Chemical Compound Neutrality
Chemical compounds are generally electrically neutral. This means that the sum of positive and negative charges in any given compound must equal zero. In the case of \( \text{Fe}_7\text{S}_8 \), we notice sulfur carries a consistent charge of \(-2\), contributing a total of \(-16\) to the compound from eight sulfur atoms. To balance this, the positive charge from iron atoms must add up to \(+16\). Neutrality is essential in understanding how elements in a compound interact. It ensures that the properties of the compound remain stable and predictable across various environments and reactions. Once you understand the principle of neutrality, determining the composition and behavior of complex compounds becomes much more straightforward.
Charge Balancing in Compounds
Charge balancing is a fundamental concept in chemistry, especially when dealing with compounds involving multiple elements with different oxidation states. In any stable compound, the sum total of positive charges must balance exactly with the sum total of negative charges. This balance keeps the compound stable. In \( \text{Fe}_7\text{S}_8 \), after calculating the negative charge from sulfur as \(-16\), the challenge was to adjust the positive charge from iron to match it. Using the positive oxidation states of \(+2\) and \(+3\), a system of equations was created to find the right combination of \( \text{Fe}^{2+} \) and \( \text{Fe}^{3+} \) ions to achieve this balance, thereby ensuring the compound's neutrality and stability.
Oxidation State Calculations
Calculating oxidation states involves determining the charge on atoms within a molecular structure, balancing needed to understand the compound's behavior and characteristics. For iron sulfide, recognizing the oxidation states of iron in this compound is crucial. Sulfur, having an oxidation state of \(-2\), sets up part of the equation. Each \( \text{Fe}^{2+} \) atom contributes \(+2\) and each \( \text{Fe}^{3+} \) contributes \(+3\). To find the right balance, observe that the sum of all oxidation states must equal zero because the compound is neutral. Solving equations for both the number of iron atoms \( \text{Fe}_7 \) and their overall charge \(+16\) allows for direct calculation of the oxidation state ratio and explains how atoms arrange to form stable structures.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A \(0.608-\mathrm{g}\) sample of fertilizer contained nitrogen as \end{tabular} ammonium sulfate, \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4}\). It was analyzed for nitrogen by heating with sodium hydroxide. \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4}(s)+2 \mathrm{NaOH}(a q) \longrightarrow\) $$ \mathrm{Na}_{2} \mathrm{SO}_{4}(a q)+2 \mathrm{H}_{2} \mathrm{O}(l)+2 \mathrm{NH}_{3}(g) $$ The ammonia was collected in \(46.3 \mathrm{~mL}\) of \(0.213 \mathrm{M} \mathrm{HCl}\) (hydrochloric acid), with which it reacted. $$ \mathrm{NH}_{3}(g)+\mathrm{HCl}(a q) \longrightarrow \mathrm{NH}_{4} \mathrm{Cl}(a q) $$ This solution was titrated for excess hydrochloric acid with \(44.3 \mathrm{~mL}\) of \(0.128 \mathrm{M} \mathrm{NaOH}\). $$ \mathrm{NaOH}(a q)+\mathrm{HCl}(a q) \longrightarrow \mathrm{NaCl}(a q)+\mathrm{H}_{2} \mathrm{O}(l) $$ What is the percentage of nitrogen in the fertilizer?

Determine the oxidation numbers of all the elements in each of the following compounds. (Hint: Look at the ions present.) a. \(\mathrm{Mn}\left(\mathrm{ClO}_{3}\right)_{2}\) b. \(\mathrm{Fe}_{2}\left(\mathrm{CrO}_{4}\right)_{3}\) c. \(\mathrm{HgCr}_{2} \mathrm{O}_{7}\) d. \(\mathrm{Co}_{3}\left(\overline{\mathrm{PO}}_{4}\right)_{2}\)

A barium mineral was dissolved in hydrochloric acid to give a solution of barium ion. An excess of potassium sulfate was added to \(50.0 \mathrm{~mL}\) of the solution, and \(1.128 \mathrm{~g}\) of barium sulfate precipitate formed. Assume that the original solution was barium chloride. What was the molarity of \(\mathrm{BaCl}_{2}\) in this solution?

An alloy of iron and carbon was treated with sulfuric acid, in which only iron reacts. \(2 \mathrm{Fe}(s)+3 \mathrm{H}_{2} \mathrm{SO}_{4}(a q) \longrightarrow \mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{3}(a q)+3 \mathrm{H}_{2}(g)\) If a sample of alloy weighing \(2.358\) g gave \(0.1352 \mathrm{~g}\) of hydrogen, what is the percentage of iron in the alloy?

A sample of \(\mathrm{CuSO}_{4} \cdot 5 \mathrm{H}_{2} \mathrm{O}\) was heated to \(110^{\circ} \mathrm{C}\), where it lost water and gave another hydrate of copper(II) ion that contains \(32.50 \%\) Cu. A \(98.77-\mathrm{mg}\) sample of this new hydrate gave \(116.66 \mathrm{mg}\) of barium sulfate precipitate when treated with a barium nitrate solution. What is the formula of the new hydrate?

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.