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Auralith Learning

Year 8 · Science · Elements, compounds and the periodic table · Lesson 3

The periodic table

How the periodic table is arranged, finding groups and periods, metals and non-metals, group names, Mendeleev's work, and spotting trends.

Whiteboard video lesson: The periodic table

25-minute video lesson

Teaching, worked examples and 20 practice questions solved step by step.

Watch free for a month

What your child will learn

  • Describe how the periodic table is arranged
  • Find the group and period of an element
  • Use the table to decide if an element is a metal
  • Explain why Mendeleev left gaps
  • Describe and use trends in a group

The method

  1. Elements are arranged in order of atomic number.
  2. Rows are periods; columns are groups.
  3. Metals are left of the staircase line, non-metals to the right.
  4. Elements in the same group have similar properties.

Key words: periodic table, group, period, atomic number, metal, non-metal, Mendeleev, trend.

Worked examples

The first three practice questions from the lesson, with every step.

Question 1

Use the periodic table. Which group and which period is sodium (Na) in?

  1. Step 1: Find the element
  2. Step 2: Row: period 3
  3. Step 3: Column: group 1

Answer: Group 1, period 3

Question 2

Use the periodic table. Which group and which period is chlorine (Cl) in?

  1. Step 1: Find the element
  2. Step 2: Row: period 3
  3. Step 3: Column: group 7

Answer: Group 7, period 3

Question 3

Use the periodic table. Which group and which period is carbon (C) in?

  1. Step 1: Find the element
  2. Step 2: Row: period 2
  3. Step 3: Column: group 4

Answer: Group 4, period 2