Practice Set
Chemistry Set 6
Answer 48 questions in one focused session, then review your score, accuracy, and explanations immediately.
Set 648 questionsAnswered 0Question 1 / 48Medium
Set 6
Question 1
Medium
An isotope has 20 protons and 21 neutrons. What is its mass number?
Question 1 of 48. Select an answer, then keep moving while the controls stay in view.
Practice summary
Focus mode, topics, and quick set guidance.
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Practice summary
Focus mode, topics, and quick set guidance.
Stay in one set, answer in any order, and submit when you want a score with explanations.
Topics: Atomic Structure, Moles, Ideal Gas Law, Solutions
Question navigator
Jump to any question when you want to review or change direction.
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Question navigator
Jump to any question when you want to review or change direction.
Next steps
Open supporting pages only when you need them.
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Next steps
Open supporting pages only when you need them.