Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid, or gaseous solvent to form a homogeneous solution of the solute in the solvent. The solubility of a substance fundamentally depends on the used solvent as well as on temperature and pressure. The extent of the solubility of a substance in a specific solvent is measured as the saturation concentration, where adding more solute does not increase the concentration of the solution.

Persuasive writing, also known as creative writing or an argument, is a piece of writing in which the writer uses words to convince the reader of his/her view regarding an issue. Persuasive writing sometimes involves convincing the reader to perform an action, or it may simply consist of an argument(s) convincing the reader of the writer’s point of view. Persuasive writing is one of the most used writing types in the world. Persuasive writers employ many techniques to improve their argument and show support for their claim. Simply put, persuasive writing is "an essay that offers and supports an opinion".

English nouns are inflected for grammatical number - that is, if they are of the countable type, they generally have different forms for singular and plural.

In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations (positively charged ions) and anions (negative ions) so that the product is electrically neutral (without a net charge). These component ions can and monatomic ions such as fluoride, as well as polyatomic ions such as sulfate.

pH is a measure of the activity of the (solvated) hydrogen ion. p[H], which measures the hydrogen ion concentration is closely related to, and is often written as, pH. Pure water has a pH very close to 7 at 25°C. Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline. The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. Primary pH standard values are determined using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such as the silver chloride electrode. Measurement of pH for aqueous solutions can be done with a glass electrode and a pH meter, or using indicators.