Understanding The Ph Scale: Measuring Acidity, Role In Everyday Life

Name ______________________ Date_____ / _____ / _________ www.EasyTeacherWorksheets.com INTERPRETING THE pH SCALE The pH scale measures the acidity or alkalinity of solution s. The scale is centered around the pH value of 7 . A pH value of less than 7 indicates an acidic solution. A pH of 7 indicates that a solution is neutral . A pH value of greater than 7 indicates a basic solution . Acidic pH < 7, Neutral pH ~ 7.0, B asic pH > 7 C hemical compounds that change col or in the presence of certain i ons are called Indicators . P henolphthalein turns pink in the presence of a base, but stays colorless in the presence of an acid . L itmus dye turns red in the presence of an acid , but turns blue in the presence of a base. Identify whether the solutions listed below are acids or bases . Write the col or expected for each indicator (phenolphthalein, litmus dye ) when immersed and i ndicate the pH range you would expect. Solution Acid or Base Phenolphthalein Litmus pH Range Ammonia Coffee Digestive juices Drain cleaner Human blood Laundry Detergent Lemon juice Milk Rain Saliva Shampoo Soda Pop