SC4a Elements and the Periodic Table

Question 1

how did Mendeleev arrange the elements in the periodic table?

Answer 1

~in order of atomic weight
~elements with similar properties were in the same group

Question 2

why did Mendeleev leave gaps in the original periodc table?

Answer 2

he thought there must be other elements left to discover

Question 3

how did Mendeleev predict the properties of yet to be discovered elements?

Answer 3

by comparing the properties of the elements surrounding the undiscovered element

Question 4

why did Mendeleev swap iodine and tellurium?

Answer 4

because iodine’s properties were closer to group 7 than its original place with group 6

Question 5

ESQ - give two reasons why other scientists did not accept Mendeleev’s periodic table when it was first published? (2 marks)

Answer 5

his table had gaps/was incomplete 1
there was no evidence that more elements would be discovered 1
he changed the order of some elements 1