The Periodic Table

Question 1

How was the original periodic table organised?

Answer 1

• By mass
• Mendeleev left gaps for undiscovered elements to maintain the pattern of properties and predict the elements properties. He moved elements based on chemical properties, even if it didn’t fit with their masses.

Question 2

Why do group 1 metals get more reactive the further down the group you go?

Answer 2

• They all have one electron to lose
• The distance from the nucleus and the electron increases so the attraction between the opposite charges gets less
• There are more electron shells to shield the electron from the nucleus

Question 3

Why was Group 0 added on the right of the table?

Answer 3

They were discovered later and their chemistry was similar so they were all in the same group

Question 4

Transition metals?

Answer 4

• Wide range of coloured compounds, caused by their electronic structures
• Alter their electronic arrangement to form several different ions
• Useful as catalysts

Question 5

Why do halogens get less reactive the further down the group you go?

Answer 5

• They all have one electron to gain
• The distance from the nucleus and the outer shell increases so the attraction for the electron gets less
• There are more electron shells to shield the electron from the nucleus

Question 6

What are the reactions of halogens with salts?

Answer 6

-Chlorine+potassium bromide__bromine+potassium chloride
Cl2+2KBr__Br2+2KCl
-Chlorine+potassium iodide__iodine+potassium chloride
-Bromine+potassium iodide__iodine+potassium bromide