The second part of the lab procedure focused on particle size and also involved several factors.
Label each factor listed below as "variable" or
"constant."
Amount of water: constant
Reaction rate: variable
Temperature: constanty
Initial amount of tablet: constant
Particle size: variable

it's c (engineer's do their work with mechanical stuff not on any living being)

answer: option (a) is the correct answer.

explanation:

the measurement of hydrogen ions in a solution is known as ph.

if ph of a solution is less than 7 then the solution is acidic. if ph of a solution is greater than 7 then the solution is basic.

when the ph of a solution equals 7, then the solution is considered as neutral.

the ph of pure water is 7, therefore, it means that concentration of hydronium ions equals that of hydroxide ions.