The strength of an aqueous acid solution is measured by pH. where is the molar concentration of hydronium ions in the solution. A solution is acidic if its pH is less than 7. The lower the pH, the stronger the acid; for example, gastric acid, which has a pH of about 1, is a much stronger acid than urine, which has a pH of about 6. How many times stronger is an acid with a pH of 3 than an acid with pH of 5?

The Praxis Mathematics (5165 ) Exam is a test required by many states for credential candidates planning to teach mathematics at the high school level. It is a single, computer-delivered test that includes questions from two content categories.

The first content category includes Number and Quantity, Algebra, Functions and Calculus. The second content category includes Geometry, Probability and Statistics, and Discrete Mathematics.

The test consists of various question types including selected-response, numeric entry, drag-and-drop and text completion.