alkalis

n.

any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water

同义词：base

a mixture of soluble salts found in arid soils and some bodies of water; detrimental to agriculture

1. Alkalis, such as sodium hydroxide, are commonly used in industrial cleaning.
   碱性物质，如氢氧化钠，常用于工业清洁。
2. The soil needs to be treated with alkalis to neutralize its acidity.
   土壤需要用碱性物质处理，以中和其酸性。
3. Alkalis react with acids to form salts and water.
   碱性物质与酸反应生成盐和水。
4. The laboratory technician carefully handled the alkalis to avoid accidents.
   实验室技术员小心地处理这些碱性物质，以避免事故发生。