环境分析化学习题及答案

Part 1 Self-study exercises and answers

1.Write down the definition and characteristics of environmental analytical

chemistry.

Answers

环境分析化学是环境化学的一个重要组成部分，是开展环境科学研究不可缺少的基础。

它是研究环境污染物的组成、结构、状态以及含量的分析化学的一个新分支。从某种意义上讲，环境科学的发展依赖于环境分析化学的发展。

特点：涉及范围广；对象复杂；变异性；定量分析；普遍性、实用性强。

2.What is the principal factors underlying some very difficult problems to analytical

chemists in environmental analytical?

Answer

the principal factors underlying these difficulties are listed below:

a: The range of analyte types is very wide. They vary from simple inorganic species at one end of the scale to complex bio-molecules at the other.

b: Sample matrices are frequently complex and unknown. They may be solid, liquid or gaseous.

c: Analytes may have to be measured at very low concentrations, e.g. a few ppb(μg. kg-1).

d: Environmental programmes often generate very large number of samples and place a premium on automation.

e: Some analyses can only be made at, or very close to, the sampling site.

Readily portable and robust analytical equipment or remote sensing devices are thus required.

3.Write down the stages of overall analytical process in an environmental

investigate.

Answer

a: definition of the aims；

b: selection and development of appropriate method；

c: sampling plan，sample collection，sample handing and pretreatment；

d: separations；

e: final measurements;

f: method validation;

g: assessment and interpretation of results;

h:safety.

4.How to select an analytical method？

Answer

In order to select an appropriate method, a whole range of factors needs to be taken into account in this selection process, some of the important factors are listed below:

a: what is the analyte?

b: detection limits.

c: precision.

d: accuracy.

e: turn-round time.

f: are analyses needed ‘on-site’?

g: number of sample and any consequent automation. h: cost.