C4 The Periodic Table Flashcards
How is the modern periodic table ordered?
by atomic number
How were early lists of elements ordered?
by atomic mass
Why did Mendeleev swap the order of some elements
to group them by their chemical properties
Why do elements in a group have similar properties
as they have the same number of electrons in the outermost shell
What name is given to group one metals?
Alkali metals
Why are alkali metals named alkali metals?
they are metals that when they react with water form an alkali
metal + oxygen –>
metal oxide
metal + chlorine –>
metal chloride
metal + water –>
metal hydroxide + hydrogen
Why does the reactivity of alkali metals increase as you go down the group?
they are larger atoms so the outermost electron is further away from the nucleus, meaning there are weaker electrostatic forces of attraction SO it is easier to lose the electron
What name is given to group 7 element?
Halogens
How does the melting point of halogens change as you go down the group?
melting point increases
How does reactivity change as you go down the halogen group?
decreases in reactivity
Why does reactivity decrease as you go down group 7?
they are larger atoms so the outermost electron is further away from the nucleus, meaning there are weaker electrostatic forces of attraction SO it is harder to gain an electron
What is a displacement reaction?
when a more reactive element takes the place of a less reactive one in a compoud
