Electrical conductivity quiz: solution

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Question 1:
Three causes of high electrical conductivity readings in water samples are:

  1. removing deep-rooted vegetation
  2. increased water temperature
  3. the action of microorganisms
  4. flood irrigation of agricultural land
  5. discharge of sewage effluent into waterways.
Answer:
removing deep-rooted vegetation
flood irrigation of agricultural land
discharge of sewage effluent into waterways.

Feedback if you get this question wrong:
Some causes of high electrical conductivity include removing deep-rooted vegetation, flood irrigation and discharge of effluent into waterways.

 

Question 2:
Electrical conductivity can be tested using a conductivity meter. This is a:

  1. physical test
  2. chemical test?
Answer:
physical test

Feedback if you get this question wrong:
Electrical conductivity is a physical property. So, testing electrical conductivity is a physical test as it does not investigate chemical reactions.

 

Question 3:
What is the difference between a test for total dissolved solids (TDS) and electrical conductivity?

  1. TDS is a measure of all solids dissolved in water. Electrical conductivity is a measure of the current that flows through water due to dissolved ionic solids.
  2. TDS and electrical conductivity measure the same thing: dissolved solids concentration.
Answer:
TDS is a measure of all solids dissolved in water. Electrical conductivity is a measure of the current that flows through water due to dissolved ionic solids.

Feedback if you get this question wrong:
TDS is the total amount of dissolved solids in a volume of water. Nearly all the dissolved solids are ionic salts that are measured by testing electrical conductivity. Using electrical conductivity meters is easy and is often used in the field as an indirect measure of salinity.

 

Question 4:
Choose three pieces of safety equipment that may be required when conducting an electrical conductivity test.

  1. goggles
  2. ear muffs
  3. mask
  4. gloves
  5. a liquid waste container.
Answer:
goggles
gloves
a liquid waste container.

Feedback if you get this question wrong:
It is important to protect yourself from splashes by wearing goggles and gloves when carrying out tests. Dispose of all chemicals safely by using a liquid waste container.

 

Question 5:
What are two ways that the reliability of the test results from electrical conductivity testing be improved?

  1. conducting a fair test
  2. doing the experiment correctly in the first place
  3. repeat the test
  4. test more samples.
Answer:
repeat the test
test more samples.

Feedback if you get this question wrong:
Reliability when monitoring water quality is achieved by testing a number of samples from the same place and by repetition.

 

Question 6:
What three factors can affect accuracy of your results?

  1. using calibrated equipment
  2. engaging trained people to conduct tests
  3. following standard procedures
  4. always wear goves.
Answer:
using calibrated equipment
engaging trained people to conduct tests
following standard procedures

Feedback if you get this question wrong:
Accuracy is achieved by trained people using calibrated equipment and following a standard procedure.