MEDIUM
AS and A Level
IMPORTANT
Earn 100
Make a list of acidic, basic and amphoteric oxides.
Important Questions on Periodicity
HARD
AS and A Level
IMPORTANT
Why do you think that elements such as copper and lead were the first to be extracted but it was not until about 200 years ago that sodium and potassium were extracted?
MEDIUM
AS and A Level
IMPORTANT
Neither the noble gases nor the radioactive elements in Period 7 appear in Mendeleev's table because they had not been discovered. What features of these elements do you think made their discovery difficult?
EASY
AS and A Level
IMPORTANT
Which element is found in Period 4, Group 17?
MEDIUM
AS and A Level
IMPORTANT
The relative atomic masses of tellurium () and iodine () are 128 and 127, respectively. Why did this present a problem to Mendeleev when he was constructing his Periodic Table?
MEDIUM
AS and A Level
IMPORTANT
Why are the elements in Groups 1 and 2 known as '-block elements', whereas those in Group 17 are called '-block elements'?
MEDIUM
AS and A Level
IMPORTANT
By looking at the elements in Period 2 of the Periodic Table and using your knowledge of Period 3 elements, predict and explain the relative sizes of the atomic radii of lithium and fluorine.
MEDIUM
AS and A Level
IMPORTANT
By looking at the elements in Period 2 of the Periodic Table and using your knowledge of Period 3 elements, predict and explain the relative sizes of a lithium atom and its ion, .
EASY
AS and A Level
IMPORTANT
By looking at the elements in Period 2 of the Periodic Table and using your knowledge of Period 3 elements, predict and explain the relative sizes of an oxygen atom and its ion, .
