C2: The Periodic Table Flashcards
How are elements in the periodic table arranged? Why?
In atomic number. This is so elements with similar properties are in columns (groups)
What do elements in the same group have in common?
The same number of electrons on its outer shell
How were elements in the periodic table arranged before the discovery of subatomic particles?
In order of atomic weights
How did Mendeleev overcome some of the problems from the early periodic table?
Left gaps for undiscovered elements
Why was the order of elements based on atomic weight not always correct?
Because of the knowledge of isotopes
What elements react to form positive ions?
Metals
Describe the relationship between boiling point and noble gases as you go down the group
As you go down the group, the boiling point increases
Describe the relationship between reactivity and the alkali metals as you go down the group
As you go down the group, reactivity increases
Are the halogens metals or non metals?
Non-metals
Describe the relationship between melting and boiling point, and the halogens as you go down the group
As you go down the group, melting and boiling point increases
What are 3 properties of transition metals?
They have ions with different charges, form coloured compounds and can be used as catalysts
What are the physical properties of metals?
Good conductors of heat, high melting and boiling points and are shiny
What are physical properties of non-metals?
Dull, brittle ad low melting and boiling points and lower densities
What are the physical properties of the alkali metals?
Soft, low densities and low melting points
Describe the relationship between melting and boiling point, and the alkali metals as you go down the group
As you go down the group, melting and boiling point decreases
