Chemistry of Water Treatment Introduction

Questions and Answers

What percentage of the earth's water is freshwater?

What are some major contaminants of concern in water purification applications?

Heavy metals, turbidity, organic compounds, pathogens

What percentage of human blood is water?

83%

What are some substances that are dissolved by water?

Gases such as oxygen, carbon dioxide, ammonia; inorganic compounds such as sodium chloride, calcium sulphate; organic substances such as humic acids, carbohydrates Signup and view all the answers

What are suspended solids defined as?

Solids that are relatively large and settle easily under quiescent conditions Signup and view all the answers

What evidence did John Snow collect during the outbreak in London?

Evidence that suggested the source of the outbreak was the public water system rather than foul air. Signup and view all the answers

How did public health concerns shift in relation to water-borne illnesses?

From preventing water-borne illnesses caused by microorganisms to considering potential health problems related to anthropogenic water pollution and the impact of water treatment on public health. Signup and view all the answers

Why was dilution in receiving streams often considered as a solution to pollution prior to industrialization?

Receiving waters were considered large enough and the mixing or detention time was considered long enough to allow the contaminants to be diluted or degraded. Signup and view all the answers

What was the prevailing belief regarding the pollution of rivers and streams prior to industrialization?

The pollution of rivers and streams was not such a significant problem. Signup and view all the answers

Why is most of the earth's surface water not readily amenable to human needs?

Although three-quarters of the earth’s surface is covered with water, most of it is not readily amenable to human needs. Signup and view all the answers