C4 The Periodic Table [Paper1] Flashcards
How is the periodic table ordered?
By atomic number
How were the early list of elements ordered?
By atomic mass
Why did Mendeleev swap the order of some elements?
To group the by their chemical properties
Why did Mendeleev leave gaps in his periodic table?
Leave room for elements that had not yet been discovered
Why do elements in a group have similar properties?
They have the same number of electrons in their outer shell
Where are metals and nonmetals located on the periodic table?
Metals to the left, non-metals to the right
What is the name given to the group 1 elements?
Alkalimetals
Why are alkali metals named this?
All metals that react with water to form an alkali
Give the general equations for the reactions of alkali metals with oxygen, chlorine, and water
Metal + Oxygen —> Metal Oxide
Metal + Chlorine —> Metal Chloride
Metal + Water —> Metal Hydroxide + Hydrogen
How does the reactivity of the alkali metals change down the group?
Increases (more reactive)
Why does the reactivity of the alkali metals increase down the group?
They are larger atoms, so the outermost electron is further from the nucleus, meaning they’re a weaker electric static forces of attraction and more shielding between the nucleus and outer electron, and it’s easier to lose the electron
What name is given to the group 7 elements?
Halogens
Give the formulae for the first 4 halogens
F2, Cl2, Br2, I2
How do the melting points of the halogens change down the group?
Increase (higher melting point)
How does the reactivity of the halogens change down the group?
Decreases (less reactive)
Why does the reactivity of the halogens decrease down the group?
They are larger atoms, so the outermost shell is further from the nucleus, meaning there are a weak electrostatic forces of attraction and more shielding between the nucleus and the outer shell, and 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 compound
What name is given to the group 0 elements?
Nobel gases
Why are the Nobel gases inert?
They have full outer shelves so do not need to lose or gain electrons
How do the melting points of noble gases changed down the group?
Increase (higher melting point)
