sc4, the periodic table (paper 1 and 2)

Question 1

how did mendeleev order the periodic table

Answer 1

• increasing relative atomic mass
• he kept missing gaps in the table
• sometimes swapped elements for better suited chemical properties

Question 2

why did mendeleev leave gaps in his table

Answer 2

• some chemical and physical properties didnt line up with the increasing relative atomic mass
• so he thought other elemetns were to be discovered
• he guessed their properties

Question 3

give reasons for why early scientists didn’t believe in mendeleevs table

Answer 3

• there were gaps
• hydrogen wasn’t properly placed

Question 4

how did mosely show RAM was a physical property

Answer 4

• he fires high energy electrons at different elements
• which gave off x rays
• every step increase in atomic number, there was a step change in the energy of these x rays

Question 5

explain how ordering by relative atomic masses could be wrong

Answer 5

becuz of isotopes