Opflow Cert. Set 4

Front 1

Convert 16,912,000 liters to acre-feet

Back 1

13.7 acre-ft

Front 2

Sacrificial anodes are also called

Back 2

Galvanic anodes

Front 3

What should I head lice on a filter be after a proper backwash?

Back 3

0.5 ft

Front 4

What is it called when ions retain a specific number of water molecules when forming crystals?

Back 4

Water Of crystallization

Front 5

What is the temperature range for good nitrification to take place?

Back 5

60 degrees to 95 degrees Fahrenheit

Front 6

If a sludge cake consists of 60% solids, where did it most likely originated?

Back 6

Drying lagoon

Front 7

Thrush from a water surge almost always acts _____ to the inside surface that it pushes against.

Back 7

Perpendicular

Front 8

One of chlorine's advantages is that it

Back 8

has a persistent residual.

Front 9

The volume of a sample for coliform compliance is

Back 9

100 mL.

Front 10

Water channels will most likely occur in which type of rock?

Back 10

Limestone

Front 11

Viruses are considered

Back 11

colloidal solids

Front 12

The most probable reason for an aerobic digester to have an odor problem is

Back 12

The supply of oxygen is insufficient

Front 13

The streaming current detector is based on what principle?

Back 13

Electromotive principal

Front 14

A double replacement reaction is the same as

Back 14

an ionic reaction

Front 15

The purple or green sulfur bacteria

Back 15

are able to photosynthesize

Front 16

Usually, which type of hydrant is a flush hydrant?

Back 16

Dry-barrel hydrant

Front 17

Which type of pipe would most likely collapse or become distorted under a partial vacuum?

Back 17

Steel

Front 18

What's pressure head caused by?

Back 18

Water flow

Front 19

Sulfur can have the following numbers associated with it: -2, +4, and +6. What do these numbers represent?

Back 19

Possible valences & The charge

Front 20

Disinfection chemicals must conform to standards set by

Back 20

NSF International and AWWA