C1 - Atomic Structure & Periodic Table

whats an element

substance made of only one type of atom

how can mixtures be seperated

filtration, simple distillation, crystallisation, fractional distillation, evaporation, condensation, chromatography

what is the charge and mass of a proton

mass = 1

charge = +1

what is the mass and charge on a neutron

mass = 1

charge = 0

what is the mass and charge of an electron

mass = very small

charge = -1

what is the atomic number of an atom

number of protons

what is the mass number of an atom

number of protons and neutrons

why are atoms neutrally charged

protons and electrons cancel out

how many electrons can go in each shell

2,8,8,2

what does the group number tell you about the electrons in an atom

how many electrons in the outer shell

what can the period tell you about the electrons in an atom

how many shells an atom has

how did dalton describe atoms

solid sphere

describe the plum pudding model by j.j thompson

a cloud of positive charge with negative electrons embedded through out

what did the gold foil ( alpha particle scattering ) experiment prove

atoms have a dense nucleus with positive charge

what did chadwick discover

the neutron

what did bohr’s experiment show

that electrons are in shells

how big are atoms

0.1nm

what are isotopes

atoms of the same element with the same number of protons but different number of neutrons

in the modern periodic table how are the atoms arranged

by their atomic number and in groups according to their chemical properties

how did mendeleev order elements

by atomic weight

why did mendeleev leave gaps in his periodic table

for elements that had no been discovered yet

what’s the name of group 1

alkali metals

what the name of group 7

halogens

what’s the name of group 0

noble gasses

why are group 0 elements unreactive

they are inert (inactive & un reactive) because they have full outer shells so they don’t need to gain or lose electrons

why are group 1 elements more reactive when you go down the group

more shells/ larger atomic radius so weaker electrostatic force of attraction between the outer shell to the nucleus so it is easier to lose an electron

how does the boiling point of group 7 elements change going down the group

increases

why do group 7 elements get less reactive going down the group

more shells/ larger atomic radius so weaker electrostatic force of attraction between the nucleus and outer shell so it’s harder to gain an electron