State Mendeleev’s periodic law. [1 MARK]
Each point: 1 Mark Mendeleev's periodic law states that properties of elements are periodic functions of their atomic masses.
Why did Mendeleev leave gaps in his periodic table? [2 MARKS]
What were the criteria used by Mendeleev in creating his periodic table? [3 MARKS]
State Ohm’s law. [1 MARK]