menu
Hit Return to see all results
Chapter 19, Problem 113SCQ
BuyFindarrow_forward

Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074

Solutions

Chapter
Section
BuyFindarrow_forward

Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074
Textbook Problem

A hydrogen-oxygen fuel cell operates on the simple reaction H 2 ( g )  +  1 2  O 2 ( g ) →  H 2 O ( l ) If the cell is designed to produce 1.5 A of current and if the hydrogen is contained in a 1.0-L tank at 200 atm pressure at 25 °C, how long can the fuel cell operate before the hydrogen runs out? (Assume there is an unlimited supply of O2.)

Interpretation Introduction

Interpretation:

The time of fuel cell operate before the hydrogen runs out has to be determined.

Concept introduction:

The Faraday’s first law of electrolysis state that the mass of the substance (m) deposited at any electrode is directly proportional to the charge (Q) passed. The mathematical form of the Fraday’s first law is written as’

m=(QF)(MZ)

Here,

The symbol F is the Faraday’s constant.

The symbol M is the molar mass of the substance in grams per mol.

The symbol Z is the valency number of ions of the substance (electrons transferred per ion).

In the simple case of constant current electrolysis, Q=I×t leading to

m=(I×tF)(MZ) (1)

The above formula is written in terms of the number of moles (n),

n=(I×tF)(1Z) (2)

Here, t is the total time the constant current (I) is applied.

The ideal gas law is written as,

PV=nRT (3)

Here,

The pressure of the gas is P.

The volume of the gas container is V.

The number of moles of gas particles is n.

The temperature is T.

The gas constant is R.

Explanation

Given:

The pressure of the gas is 200â€‰atm.

The volume of the gas container is 1â€‹â€‰L.

The temperature is 298â€‰K.

The gas constant is R=0.0821â€‰atmâ‹…Lâ‹…molâˆ’1â‹…Kâˆ’1.

The constant current is 1.5â€‰A.

The faradayâ€™s constant F is equal to 96500â€‰Câ‹…molâˆ’1.

The hydrogen-oxygen fuel cell reaction is written as,

Â Â Â Â H2(g)+12O2(g)â†’H2O(l)

Here, Z=2

Substitute the value of pressure, volume, temperature and gas constant in equation (3) to calculate the number of moles of hydrogen,

(200â€‰atm)(1â€‹â€‰L)=n(0

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Additional Science Solutions

Find more solutions based on key concepts

Show solutions add

How can errors in the cell cycle lead to cancer in humans?

Human Heredity: Principles and Issues (MindTap Course List)

Where would you look for a continental rise? What forms continental rises?

Oceanography: An Invitation To Marine Science, Loose-leaf Versin