C2 - Periodic Table Flashcards
C2 - What are the Patterns and trends in the periodic table.
Vertical columns are called groups.
Atoms in the same group have the same number of electrons in their outer shell.
The group number is the same as the number of electrons in the outer shell e.g. atoms in group 1 all have 1 outer electron.
Horizontal rows are called periods.
Atoms in the same period have the same number of electron shells.
The period number tells you how many shells there are in the atom e.g. atoms in the second row of the periodic table have two electron shells.
C2 - What conclusions were made from Ernest Rutherford’s gold foil experiment?
Most alpha particles passed straight through = most of the atom is just empty space.
Some alpha particles deflected = small, central, positively charged region called the nucleus.
Alpha particles are fast moving with a large momentum and still deflected by large distances = nucleus must have a large mass in order to stop the alpha particles.
C2 - Describe and explain the pattern of reactivity in group 1 alkali metals
The atoms of each element get larger going down the group.
The outer shell electron gets further away from the nucleus and is shielded by more electron shells.
The further an electron is from the positive nucleus, the easier it can be lost in reactions.
Reactivity increases as you go down the group.
C2 - Describe and explain the pattern of reactivity in group 7 halogens.
The atoms of each element get larger going down the group.
The outer shell gets further away from the nucleus and is shielded by more electron shells.
The further the outer shell is from the positive attraction of the nucleus, the harder it is to attract another electron to complete the outer shell.
Reactivity decreases as you go down the group
