By Lauren Whitney | Updated Aug 30, 2022
To a chemist, a base is an electron pair donor. In everyday terms it’s the alkaline counterpart of an acid, and when the two meet they neutralize each other. The pH scale, ranging from 0 to 14, assigns any substance with a pH greater than 7 as a base. Though the word “base” might sound technical, the materials themselves are common in most kitchens, bathrooms, and laundry rooms.
Baking soda (NaHCO3) has a pH of 8.3, slightly alkaline compared to distilled water (pH 7.0). It’s a staple in baking, where it reacts with acids to lift dough. Outside the oven, it deodorizes drains, cleans surfaces, and serves as a gentle, non‑toxic abrasive. A teaspoon in a cup of water produces the characteristic slickness of a base, and a small dose can soothe mild stomach acidity. Because it’s safe to touch, baking soda is a go‑to household cleaner.
Historically used to preserve mummies, borax (Na2B4O7·10H2O) now appears in laundry detergents and pest‑control sprays. Its pH of 9.2 makes it 920 times more alkaline than pure water. When dissolved, borax releases borate ions that combine with oxygen to form trace hydrogen peroxide, giving it mild disinfectant and bleaching properties. While contact with skin can cause irritation, borax is mildly toxic if ingested, so it should be stored out of reach of children.
Milk of Magnesia is a classic antacid and laxative. The powdered formulation of magnesium hydroxide (Mg(OH)2) appears milky and has a pH of 10.5. Commercial products often mask the bitter taste of alkalis with mint or fruit flavors, but the underlying chemistry remains the same: a base that neutralizes excess stomach acid.
In a household setting, “ammonia” usually refers to a 5–10% solution of ammonium hydroxide (NH4OH), a clear liquid with a pH of 11. It is a powerful cleaner that dissolves grease and grime on virtually any surface. Although trace amounts of ammonia can appear in some sodas, it is best used alone: mixing it with other cleaners can generate toxic fumes.
Lye, or sodium hydroxide (NaOH), is the strongest base commonly available for home use. Its pH exceeds 13, and it is employed in drain‑clearing agents, oven cleaners, and even in the traditional process of turning corn into grits. Because lye is caustic, it can cause severe chemical burns on skin and eyes; always wear gloves and eye protection when handling.
