what is a base in chemistry let's start with the difference between an acid and a base the acidity of a solution is measured by its number of hydrogen ions you can look up this measure on a pH scalar the abbreviation pH stands for potential hydrogen and it's a measure of how much hydrogen is in the solution and how active the hydrogen ion is hydrogen ions determine whether a solution is an acid or a base a base that is water soluble is called an alkali acids are hydrogen ion donors and alkalis are hydrogen receptors a substance with a pH lower than seven is considered acidic and greater than Saturn 7 is an Alkali seven is neutral each interval on the pH scale is a 10-fold increase so a solution with a pH of 5 is 10 times more acidic than an object with a pH of 6. the difference between an acid and a base comes down to the number of positively charged hydrogen ions when an acidic substance is dissolved in water it releases hydrogen ions causing an increased proportion of positively charged ions when an Alkali substance dissolves in water it releases negatively charged particles called hydroxide ions remember an Alkali is a base that is water soluble again acids are called hydrogen ion donors and bases are hydrogen ion receptors let's look at a couple characteristics of acids acids taste sour acids turn blue litness paper red acidic Solutions have a pH less than seven characteristics of bases basis tastes bitter they feel slippery bases turn red litmus paper blue and basic Solutions have a pH greater than seven acids typically have a hydrogen in front of it with their chemical formula HCL is hydrochloric acid HF is hydrofluoric acid and bases typically have a hydroxide ion NaOH is sodium hydroxide and is a base and Koh is potassium hydroxide and is also a base hope that was helpful thanks for watching and remember kindness multiplies kindness be kind to someone today