Create a visual lesson
~2 minAcid vs. Base: What's the Difference?
Read the comparison below, or explore it visually. Create a visual lesson comparing acid and base using available credits or plan allowance.
Acids and bases are chemical opposites, and the difference comes down to pH and ions. An acid releases hydrogen ions (H⁺) in water and has a pH below 7; a base releases hydroxide ions (OH⁻) and has a pH above 7. Mix the two and they neutralize each other, forming water and a salt.
At a glance
| Acid | Base | |
|---|---|---|
| pH | Below 7 | Above 7 |
| Releases | Hydrogen ions (H⁺) | Hydroxide ions (OH⁻) |
| Taste | Sour (lemon, vinegar) | Bitter (soap, baking soda) |
| Feel | Can be corrosive | Slippery, soapy |
| Example | Hydrochloric acid, citric acid | Sodium hydroxide, baking soda |
Which should you use?
Acid
It's an acid when it releases hydrogen ions, tastes sour, and sits below 7 on the pH scale — like lemon juice, vinegar, or stomach acid.
Base
It's a base when it releases hydroxide ions (or accepts hydrogen ions), feels slippery, and sits above 7 — like soap, baking soda, or antacids.
Frequently asked questions
What happens when you mix an acid and a base?
They neutralize each other, producing water and a salt. That's why antacids (bases) relieve acid indigestion by canceling out excess stomach acid.
What is pH?
pH is a 0–14 scale of how acidic or basic a solution is. Below 7 is acidic, exactly 7 is neutral (pure water), and above 7 is basic.
Is a base the same as an alkali?
An alkali is a base that dissolves in water. All alkalis are bases, but not every base dissolves well, so they're not exactly the same.