Find study content
Learning Materials

Discover learning materials by subject, university or textbook.

Explanations

Textbooks

Exams
All Subjects

Anthropology

Archaeology

Architecture

Art and Design

Bengali

Biology

Business Studies

Greek

Chemistry

Chinese

Combined Science

Computer Science

Economics

Engineering

English

English Literature

Environmental Science

French

Geography

German

History

Hospitality and Tourism

Human Geography

Italian

Japanese

Law

Macroeconomics

Marketing

Math

Media Studies

Medicine

Microeconomics

Music

Nursing

Nutrition and Food Science

Physics

Polish

Politics

Psychology

Religious Studies

Sociology

Spanish

Sports Sciences

Translation

All Subjects

Biology

Business Studies

Chemistry

Combined Science

Computer Science

Economics

English

Environmental Science

Geography

History

Math

Physics

Psychology

Sociology

EXAM TYPES

GCSE

IGCSE

AS

A Level

International A Level

University Admissions Tests

GCSE SUBJECTS

GCSE 1

GCSE 2

GCSE 3

GCSE 4

GCSE 5

SOME-TEXT

IGCSE SUBJECTS

IGCSE 1

AS SUBJECTS

AS 1

A Level SUBJECTS

A Level 1

International A Level SUBJECTS

International A Level 1

University Admissions Tests SUBJECTS

University Admissions Tests 1
Features
Features

Discover all of these amazing features with a free account.

Flashcards

Vaia AI

Notes

Study Plans

Study Sets
What’s new?

Flashcards
Study your flashcards with three learning modes.

Study Sets
All of your learning materials stored in one place.

Notes
Create and edit notes or documents.

Study Plans
Organise your studies and prepare for exams.
Resources
Discover

All the hacks around your studies and career - in one place.

Find a job

Find a degree

Student Deals

Magazine

Mobile App
Featured

Magazine
Trusted advice for anyone who wants to ace their studies & career.

Job Board
The largest student job board with the most exciting opportunities.

Vaia Deals
Verified student deals from top brands.

Our App
Discover our mobile app to take your studies anywhere.

Go to App

Learning Materials

Features

Discover

Chapter 27: Q22 P (page 768)

A mixture containing only ${Al}_{2} O_{3}$ (FM 101.96) and ${Fe}_{2} O_{3}$ (FM 159.69) weighs 2.019 g. When heated under a stream of $H_{2} {Al}_{2} O_{3}$ is unchanged, butis ${Fe}_{2} O_{3}$ converted into metallic Fe plus $H_{2} O (g)$ If the residue weighs 1.774 g, what is the weight percent of ${Fe}_{2} O_{3}$ in the original mixture?

Short Answer

Expert verified

The weight percent of ${Fe}_{2} O_{3}$ is 0.404%.

Step by step solution

01

Calculate the weight percent:

From the question we can consider the reaction as,

${Fe}_{2} O_{3} + {Al}_{2} O_{3} + heat \to Fe + {Al}_{2} O_{3}$

Consider,

localid="1663665835168" $m_{1} ({Fe}_{2} O_{3} + {Al}_{2} O_{3})$ as 2.019g,

$m_{2} (Fe + {Al}_{2} O_{3})$ as 1.774g

Mass of lost oxygen is $m (O) = m_{1} - m_{2}$

$m (O) = 2.019 g - 1.774 g m (O) = 0.245 g 0.245 g o f o x y g e n = 0.01531 m o l e s$

Calculate the moles of localid="1663665958980" ${Fe}_{2} O_{3}$

$n ({Fe}_{2} O_{3}) = \frac{1}{3} \times n (O) n ({Fe}_{2} O_{3}) = \frac{1}{3} \times 0.01531 mol n ({Fe}_{2} O_{3}) = 0.005105 mol$

So the weight percentage is

$w t % = \frac{m (F e_{2} O_{3})}{m (s a m p l e)} w t % = \frac{0.815 g}{2.019 g} w t % = 0.404$

The weight percent of $F e_{2} O_{3}$ is 0.404%.

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.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

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 50.00-mL solution containingwas treated with excess AgNo₃ to precipitate 0.2146 g of AgBr (FM 187.772). What was the molarity of NaBr in the solution?

To find the Ce⁴⁺ content of a solid, 4.37 g were dissolved and treated with excess iodate to precipitate Ce(IO₃)_4. The precipitate was collected, washed well, dried, and ignited to produce 0.104 g of CeO₂ (FM 172.114). What was the weight percent of Ce in the original solid?

The thermogravimetric trace on the next page shows mass loss by $Y_{2} (OH)_{5} Cl \cdot {xH}_{2} O$ upon heating. In the first step, waters of hydration are lost to give ~8.1% mass loss. After a decomposition step,19.2% of the original mass is lost. Finally, the composition stabilizes at $Y_{2} O_{3}$ above $800^{9} C$ .

(a) Find x in the formula $Y_{2} (OH)_{5} Cl \cdot {xH}_{2} O .$ Because the 8.1% mass loss is not accurately defined in the experiment, use the 31.8% total mass loss for your calculation.

(b) Suggest a formula for the material remaining at the 19.2% plateau. Be sure that the charges of all ions in your formula sum to 0 . The cation is $Y^{3 +}$ .

${LaCoO}_{3 + x}$ , has a perovskite structure (Box 19-1) with variable oxygen content. The figure shows the thermogravimetric curve observed when 41.8724m gwere heated in role="math" localid="1665035505591" $5 vol % H_{2} in Ar . La (II)$ does not react, but cobalt is reduced to Co(s)

(a) What is the oxidation state of cobalt in the ideal formula ${LaCoO}_{3}$

(b) Write the reaction of role="math" localid="1665035588740" ${LaCoO}_{3} with H_{2}$ to produce ${La}_{2} O_{3} with (s), Co (s), and H_{2} O (s)$

(c) If $41.8724 mg of {LaCoO}_{3}$ react completely, what will be the mass of product $({La}_{2} O_{3} + (Co)$ ?

(d) Write the balanced reaction of role="math" localid="1665035782894" ${LaCoO}_{3 + x} with H_{2} O$ to produce ${La}_{2} O_{3}, Co, and H_{2} O . If 41.8724 mg of {LaCoO}_{3 + 1}$ react completely; what will be the mass of solid product? Your answer will be an expression with x in it.

(e) From the observed product mass $(37.767 mg) at 700 ° c$ , find x in ${LaCoO}_{3 + x}$ Write the formula of the starting solid.

(f) In part (c), the mass lost from the ideal formula ${LaCoO}_{3 + x}$ , is 4.0877 mg. What is the product nearrole="math" localid="1665035980286" $500 ° C$ where the mass is -40.51 mg?

Why is sample dropped into the preheated furnace before the oxygen concentration reaches its peak in Figure 27-9?

See all solutions

Recommended explanations on Chemistry Textbooks

Kinetics

Read Explanation

Nuclear Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Chemical Reactions

Read Explanation

Organic Chemistry

Read Explanation

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.

Sign-up for free