Briefly describe how a potentiometric pHmeter works. (Hint: Describe how the pH meter
measures the amount of H+ or OH- ions in a sample)

A potentiometric pH meter is used to measure the pH of a solution.

Explanation:

A pH meter is an common instrument that is used to measure the hydrogen-ion concentration in aqueous solutions , the meter indicates its acidity or alkalinity and is expressed as pH.

The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, hence the pH meter is often called a potentiometric pH meter. The difference in electrical potential is related to the pH of the solution.

Potentiometric pH meters consists of a simple electronic amplifier and a pair of electrodes, alternatively it may consist of a combination electrode, and some form of display calibrated in pH units. It usually has a glass electrode and a reference electrode, or a combination electrode. The electrodes, or probes, are inserted into the solution to be tested and pH values are read off.

d. temperate deciduous forest

the answer for sodium is 0.186

the answer for rubidium is 0.251