Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. 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. Is AP Chemistry hard AP Chemistry consistently ranks as one of the hardest AP classes.

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. Created by experts, Khan Academy’s library of trusted, standards-aligned practice and lessons covers math K-12 through early college, grammar, science, history, AP, SAT, and more. Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. For other students, the AP Chemistry course fulfills the laboratory science requirement and frees time for other courses.

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Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere. The average atomic mass of an element is calculated by taking the weighted average mass of the element's naturally occurring isotopes. Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Because they contain different numbers of neutrons, isotopes have different atomic masses. Isotopes are atoms of the same element with different numbers of neutrons.

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