What does the pH measured of?

• the levels of nitrates and phosphates

• the levels of phosphates

• how acidic or basic the water is

• how salty the water is

Pure water is good conductor of electricity.

• True

• False

What is alkalinity?

• Ability to neutralize a base

• Presence of H⁺ ions

• Ability to neutralize an acid

• Presence of Ca²⁺ ions

Which ion is responsible for alkalinity?

• . Mg²⁺

• Ca²⁺

• Cl^-

• OH^-

What are the indicators used in the estimation of alkalinity?

• EBT and starch

• Phenolphthalein and methyl orange

• Phenolphthalein and EBT

• methyl orange and starch

Which of the following indicator gives pink colour in basic medium?

• Methyl orange

• Starch

• EBT

• Phenolphthalein

With respect to the constituents causing alkalinity in water, which of the following situation never arises?

• CO₃^2- and HCO₃^– together

• HCO₃^– and OH^– together

• OH^– only

• OH^– and CO₃^2- together

Colder water.....

• hold MORE dissolved oxygen

• holds LESS dissolved oxygen

What is the colour change for the titration for Dissolved Oxygen determination?

• Blue to colourless

• Colourless to blue

• Yellow to Blue

• Blue to yellow

The method used for determination of dissolved oxygen is called as

• Iodimetric method

• Wrinkler method

• Alsterberg method

• Volumetric method