Unit 4

Question 1

How can THMs be removed from water ?

Answer 1

Charcoal

Question 2

Why are THMs not allowed in water at levels above 80 ppb?

Answer 2

Can cause cancer

Question 3

Ground water is impure and contains hardness ions.When does the water gain these ions.

Answer 3

Filtration when it rains

Question 4

When ion exchange resin in a water softener is regenerated it (gains or loses)

Answer 4

Loses

Question 5

Hardness ions (gain or losses) sodium ions

Answer 5

Gains

Question 6

The name of the susbstance added during water treatment to kill germs and prevent diseases is?

Answer 6

Chlorine

Question 7

In water treatment this process removes objects large objects like pop cans,stick,etc?

Answer 7

Screening

Question 8

Some communities add Florine to thier drinking water supply’s?why?

Answer 8

So it can be healthier,reduce teeth decay

Question 9

Why is adding chlorine to water through the post-chlorination step a concern?

Answer 9

Can cause forigen THM’s

Question 10

The process of removing large particles from the water before treatment at a municipal water plant is known as?

Answer 10

Screening

Question 11

In the lab if there were calcium ions remaining in the filtrate,a _______ removed formed whe. Sodium carbonate was added to the filtrate

Answer 11

Precipitate

Question 12

Ion exchange resin possesses an attraction for

Answer 12

Mg,Ma,Fe,Ca

Question 13

The method if water softening which involves passing hard water through a resin like that found water-softening unit is called?

Answer 13

Reverse osmosis

Question 14

Converts dissolved orgaic susbstance a to few simple compounds.

Answer 14

Bacterial action

Question 15

Removes ONLY large “suspended” particles?

Answer 15

Sand and gravel

Question 16

REMOVES large “suspended” particles and dissolved substances?

Answer 16

Condensation and evaporation

Question 17

If groundwater is slightly acidic (a ph of less than 7) as it filters down through gravel and sand, what could happened?

Answer 17

Pick up hard water ions

Question 18

Hard water caused by whoa things

Answer 18

Mg,Cl

Question 19

The removing of hard water ions from our water supply is known as what process.

Answer 19

Water softening

Question 20

Hard water ions

Answer 20

Prevent soap from cleaning very well

Question 21

The rock line scale found on inside of hot water heaters used to boil hard water is

Answer 21

Bad takes more energy to heat water

Question 22

The removal of hard water ions from our water supply is known as what process

Answer 22

Water softening

Question 23

As the amount of hard water ions in a water sample decreases

Answer 23

The solubility of soap increase

Question 24

During which part of the hydrologic cycle are dissolved heavy metals,minerals,or molecule substances removed?

Answer 24

Evaporation in water