C4 - The Periodic Table (PAPER 1) Flashcards
How is the modern Periodic Table ordered
by atomic number
How were the 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 did Mendeleev leave gaps in his Periodic Table
leave room for undiscovered elements
Why do elements in a group have similar chemical properties
Same amount of electrons in the outer shell
Where are metals and non-metals located on the Periodic Table
metals to the left, non-metals to the right
What name is given to the Group 1 elements
alkali metals
Why are alkali metals named this
metals that react with water to form alkalis
What are the general equations for the reaction of alkali metals with
- oxygen
- chlorine
- water
metal + oxygen -> metal oxide
metal + chlorine -> metal chloride
metal + water -> metal hydroxide + hydrogen
How does the reactivity of alkali metals change down the group
increases (more reactive)
Why does the reactivity of alkali metals increase down the group
- they are larger atoms,
- outermost electron is further from the nucleus
- weaker electrostatic forces of attraction
- easier to lose electron
What is the name given to group 7 elements
halogens
What are the formula of the first four halogens
F2, Cl2, Br2, I2
How do the melting points of the halogens change down the group
increase (higher m.p.)
How does the reactivity of halogens change down the group
decrease (less reactive)
