Courses
Teacher-curated, self-paced courses. Looking for a guided sequence through a full topic? See Learning Paths.
2 courses
Building the Periodic Table
Chemistry · High School (11–12) · Development of the Periodic Table, Groups and Families
FreeCh 3 · 1/2
From Dobereiner's triads to Mendeleev's gaps and Moseley's atomic numbers: how the periodic table was built, how new elements are named, and how the s, p, d and f blocks follow from electron configurations.
3Lessons11Problems2Python Labs1Question Set1Mock Test
From Triads to the Modern Table
Chemistry · High School (9–10), General · Development of the Periodic Table
FreeCh 9 · 1/4
Why did chemists need a table? In this course we follow the story from Dobereiner's triads and Newlands' octaves to Mendeleev's table with its gaps, and then to the modern table, which is arranged by atomic number.
3Lessons10Problems2Python Labs1Question Set1Mock Test
The Periodic Table: Deep Dive and Challenge Practice
Chemistry · High School (9–10) · Development of the Periodic Table
StandardFirst lesson freeExtra course
You know how the table is built and how it is used. Now ask why. Why did Moseley's X-rays settle an old argument? Why does the energy to remove an electron dip twice in each period? In this course we read further, solve harder problems and take an olympiad style test.
3Lessons8Problems2Python Labs1Question Set1Mock Test
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