High-pH substances, also known as alkalis, are chemical compounds that have a pH level higher than 7. Alkalis are typically composed of bases, such as sodium hydroxide, potassium hydroxide, and calcium hydroxide, which are capable of neutralizing acids. Alkalis are commonly used in industrial processes, such as in the production of paper, soap, and detergents. They are also used in the treatment of wastewater and in the manufacture of fertilizers.