Lead-Acid Car Battery Chemical Processes

ChemistryElectrochemistry and Lead-Acid BatteriesMediumSTEM

Published:

Question

33) When a car battery (A) with an electrolyte density of ... to another car battery (B) with an electrolyte density of ...

a) The $pOH$ value of the electrolyte in battery (B) decreases.

b) Lead atoms are oxidized at the negative electrode in ...

c) The mass of both the anode and cathode materials de...

d) The mass of both the anode and cathode increases in...

This question includes visual content: A table at the top shows oxidation and reduction reactions for different scenarios (a-d). Below, there are two numbered questions (33 and 34). Question 33 is a multiple-choice question with four options (a-d). The text is partially cut off but references car batteries A and B. A handwritten checkmark or loop appears next to option 'd' in the top table.

Animated Video Solution

The first half plays free, the full solution is in the app.

Step by Step Written Solution

1
Step 1

In this problem, we are looking at a system where a car battery A is connected to another car battery B, presumably to charge it. We need to identify the correct statement from the options provided.

Electrochemistry: Charging a Car Battery

2
Step 2

A car battery is a lead-acid battery. During the charging process, the electrical energy from battery A is used to reverse the chemical reactions in battery B.

Lead-Acid Battery Basics

- Anode: Lead ($Pb$)

- Cathode: Lead dioxide ($PbO_2$)

- Electrolyte: Sulfuric acid ($H_2SO_4$)

3
Step 3

Let's examine the chemical reactions during discharge and recharge. During discharge, both electrodes are converted into lead sulfate.

Discharge Reactions

$$Pb_{(s)} + SO_4^{2-}_{(aq)} \rightarrow PbSO_4_{(s)} + 2e^- \quad \text{(Anode)}$$
$$PbO_{2(s)} + 4H^+_{(aq)} + SO_4^{2-}_{(aq)} + 2e^- \rightarrow PbSO_4_{(s)} + 2H_2O_{(l)} \quad \text{(Cathode)}$$
4
Step 4

When we charge the battery, these reactions are reversed. Lead sulfate on the negative electrode is reduced back to lead metal, and lead sulfate on the positive electrode is oxidized back to lead dioxide.

Charging Reactions

$$PbSO_4_{(s)} + 2e^- \rightarrow Pb_{(s)} + SO_4^{2-}_{(aq)} \quad \text{(Negative Electrode)}$$
$$PbSO_4_{(s)} + 2H_2O_{(l)} \rightarrow PbO_{2(s)} + 4H^+_{(aq)} + SO_4^{2-}_{(aq)} + 2e^- \quad \text{(Positive Electrode)}$$
5
Step 5

Let's evaluate the options based on these charging reactions. Option A mentions the pOH value. During charging, hydrogen ions are produced at the positive electrode, increasing the acidity, which affects pH and pOH, but this isn't the most direct consequence described.

Evaluating Options

- Option a: pOH value decreases? Acid ($H^+$) is produced, pH decreases, so pOH increases.

The rest of this solution is on Solvi

4 more steps are locked. Watch the full animated, narrated solution for free.

Snap a photo, solve any question like this.

Download on the App Store Get it on Google Play

Free to download · First solutions are on us

100K+Questions solved daily
50K+Students learning
4.8 ★App Store rating

About This Question

Subject
Chemistry
Topic
Electrochemistry and Lead-Acid Batteries
Difficulty
Medium
Exam
STEM
Question Type
Multiple Choice

Similar Questions

Doğal Belirteçler ve Asit-Baz Tanıma Acids and Bases · Medium Periyodik Sistemde Elementlerin Özellikleri Periodic System · Medium A Sıvısı Hakkında Bilgiler Madde ve Özellikleri · Medium Tanecik Türleri Sorusu Chemical Species and Solutions · Medium Periyodik Özellikler Soru Analizi Periyodik Sistem · Hard Maddelerin Birbiri İçindeki Çözünebilirliği ve Etkileşimler Karışımlar ve Çözünürlük · Easy

Solve any question in seconds

Snap a photo and AI explains it step by step with voice and animation.

Download on the App Store Get it on Google Play
Solvi
The full solution is in the appFree to download · First solutions are on us
Get