Understanding Acids and Bases

What Are Acids?

Acids are substances that release hydrogen ions (H⁺) when dissolved in water.

They taste sour (Examples: lemon juice or vinegar).
Acids have a pH of less than 7 on the pH scale.
Strong acids, like hydrochloric acid, can react with metals and even dissolve them.

Examples of Acids:

What Are Bases?

Bases are substances that release hydroxide ions (OH⁻) when dissolved in water.

Examples of Bases:

Acids, Bases & Our Body

How can acids melt metal but also be in our stomachs?

Stomach acid (hydrochloric acid) is strong enough to break down food, similar to how strong acids can dissolve metal.
Our stomach is protected by a mucus lining, preventing the acid from harming it.

Why does baking soda stop heartburn?

Baking soda is a base (sodium bicarbonate), and heartburn is caused by excess stomach acid.
When baking soda is used, it neutralizes the acid, turning it into water and salt and reducing the burning sensation.

Fun Facts

Here are some interesting facts about acids and bases:

Bee stings are acidic, so applying a base like baking soda can help neutralize the pain. Wasp stings, however, are basic, so applying vinegar (an acid) helps!
Your toothpaste has mild bases to neutralize acids produced by bacteria in your mouth, protecting your teeth from cavities.
Adding vinegar (acid) to milk causes it to curdle, which is one way to make cheese.
Carbonic acid gives soda its fizzy taste. When you open a can, carbon dioxide gas is released, forming this weak acid.

Review

Let’s quickly recap what we learned about acids and bases:

What ion do acids release? Hydrogen Ions (H+)
What ion do bases release? Hydroxide Ions (OH–)
What do acids and bases form when mixed? Salt & Water
What is the name of the process where an acid and a base cancel each other out? Neutralization

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