Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: [ Ссылка ]
The pH scale is used to determine the acidity or basicity (alkalinity) of a substance. Acidic substances have pH values below 7, while basic substances have pH values above 7; neutral substances have a pH of 7. The pH scale is logarithmic, so each step represents a 10-fold change in concentration.
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today!
Donate here: [ Ссылка ]
Volunteer here: [ Ссылка ]
