alkaline
part of speech
adjective (alkaline)
meaning for a pupil
1) Alkaline describes a substance that is the opposite of an acid: it has a pH above 7, such as soap, baking soda or bleach. tree →
2) An alkaline battery is a common kind of battery that uses an alkaline chemical inside. tree →
sense in the lessons
In science lessons, the pH scale goes from 0 to 14: acids are below 7, neutral is 7 (pure water), and alkaline is above 7. Indicators such as red cabbage juice or litmus change colour: alkalis turn red litmus blue. Strong alkalis like bleach and oven cleaner can burn skin, so safety goggles and gloves are needed. Some soils are alkaline, which matters to gardeners.
examples
- Soap is slightly alkaline. tree →
- Red litmus paper turns blue in an alkaline solution. tree →
- Baking soda makes the water alkaline. tree →
- Bleach is strongly alkaline, so handle it with care. tree →
- The TV remote uses alkaline batteries. tree →
- Some plants grow best in alkaline soil. tree →
- Our cabbage indicator turned green in the alkaline liquid. tree →
note
Adjective only. The noun is alkali (plural alkalis). Opposite: acidic. A substance that is neither is neutral. Trap: alkaline does not mean safe; strong alkalis are as dangerous as strong acids. Myth: alkaline water does not change the pH of your blood.
In the corpora
- Bacteria on teeth make acid from sugar, which damages enamel; toothpaste is slightly alkaline, and fluoride in it makes enamel tougher.
- Soap is slightly alkaline and feels slippery; strong alkalis like oven cleaner can burn skin badly.
- An indicator is a substance whose colour shows whether something is acidic or alkaline.
- Hydrangeas turn blue in acidic soil and stay pink in alkaline soil.
Trees and pragmatics
Every meaning and example of «alkaline» parsed by Mova, each sentence with its dependency tree and frames.