The elements are Krypton and Xenon
The pH value can be measured using electrochemical measuring systems, litmus paper, or indicators and colorimeters. The easiest way to take a pH measurement is to use litmus paper or a colorimeter. The advantage of this type of pH measurement is that the pH range is well known and they are easy to apply.
Answer:
It's A
Explanation:
Liquid can heat things and so can steam.
Solids have a definite shape, and a definite volume.
Liquids have a definite volume, but have no definite shape.
Gas have neither a definite volume nor a definite shape.
Hope this helps!