C1 - Atomic Structure and the Periodic Table Flashcards
Describe the structure of an atom
A nucleus in the centre with electrons in shells around
What is the charge of a proton?
+1
What is the charge of a neutron?
0
What is the charge of an electron?
-1
What is the mass of a proton?
1
What is the mass of a neutron?
1
What is the mass of an electron?
0 (1/1836)
What is the rule for amount of electrons in each shell?
2,8,8,2
What does the atomic number mean (smaller number)?
Amount of protons in an atom
What does the atomic mass mean (bigger number)?
Total amount of protons and neutrons in the nucleus of an atom
What does the term ‘electronic configuration’ mean?
How electrons are arranged
What are isotopes?
Atoms with the same number of protons but different numbers of neutrons
What is the relative atomic mass?
An average of the different isotopes
How would you calculate the relative atomic mass?
(percentagemass)+(percentagemass)etc/100
What did Mendeleev do?
Create the periodic table - arranged elements in order of mass and spotted patterns
What state are alkali metals (group 1) at room temperature?
Solid
Do alkali metals (group 1) have a high or low melting point?
Low
Are alkali metals (group 1) hard or soft?
Soft
What happens when alkali metals (group 1) react with water?
They form hydroxides and hydrogen gas. They will move, float, fizz, potassium catches fire. Equation: metal + water -> metal hydroxide + hydrogen
Why do alkali metals (group 1) get more reactive down the group?
They all want to lose the outer electron. Down the group, the outer electron is lost more easily because the atoms have more electron shells. This mean that the outer electron is further away from the nucleus so there is more shielding from inner electrons, resulting in a much weaker electrostatic attraction.
How reactive are Nobel gases?
They are all unreactive (inert)
Why are Nobel gases unreactive?
They already have a full outer shell. This means that they have many uses e.g. because they’re non-flammable
Describe fluorine’s appearance
Pale yellow gas
Describe chlorine’s appearance
Pale yellow-green gas
Describe bromine’s appearance
Brown liquid
Describe iodine’s appearance
Grey solid
What does -ine refer to?
The element, which is diatomic (X₂)
What does -ide refer to?
The anion (X-)
What do a metal + halogen produce?
Metal halide
What do hydrogen halides form when dissolved?
Acids
Why does reactivity of halogens (group 7) decrease down the group?
It’s harder to gain an outer electron, can be proved with displacement reactions e.g. sodium bromide + fluorine -> sodium fluoride + bromine
What does the group of an element mean?
The number of electrons in the outer shell
What does the period of an element mean?
The number of electron shells
