C2.1

Question 1

How did Mendeleev Mamie his periodic table

Answer 1

Arranged elements in order of increasing mass and sometimes broke the rule to make the element with similar properties were close such as iodine should be before tellurium in mass order but they are swapped to match properties. He also left gaps for elements that were yet to be discovered

Question 2

What are atoms

Answer 2

The smallest particle that can take part in chemical reactions

Question 3

What is an isotope

Answer 3

Same an atom with same number of protons as another so are same element, but has a different number of neutrons, so an isotope

Question 4

Rule for drawing electronic configurations

Answer 4

First shell only has 2 electrons opposite each other. The next shells, electrons like to be in pairs and will have a max of 4 pairs or 8 electrons in all the next shells. They spread out evenly