What measures the acidity or basicity of a solution?

The acidity or basicity of a solution is measured using the pH scale, which ranges from 0 to 14. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic. My doctor once explained how our stomach acid is around pH 1.5-3.5, which is highly acidic, to help with digestion.

It's the pH scale! You can use pH strips or a digital pH meter for precise readings. Some health trackers or apps actually recommend checking the pH of your urine or saliva as part of a 'body balance' thing, though the scientific basis for that for health is debated. But yeah, pH is the answer!

It's the pH scale. That's what tells you if something is acidic or basic.

It's the pH scale, bro. Like, from 0 to 14. Lower numbers mean acidic, higher means basic. Water is 7, neutral. We learned this in school science, pretty standard stuff.

My son learned this in his science class recently. It's called the pH scale. You use litmus paper or a pH meter. Red for acid, blue for base, if I remember correctly from his projects! It's a fundamental concept in chemistry.