atomic structure and periodic table Flashcards
what is the structure of an atom
a central nucleus containing neutrons and protons surrounded by electrons in shells
how many electrons can each shell contain
first- 2
second-8
third-8
what are the charges and masses of a proton neutron and electron
proton- 1 mass unit, +1
neutron- 1 mass unit, 0
electron- negligible(1/1840), -1
what is proton/atomic number
the smaller number represented in periodic table, and is the number of protons in the nucleus of an atom
what is mass/ nucleun numer
the larger number represented in periodic table, the total number of protons and neutrons in nucleus of atom
what is the nobel gas group and what is a caracterisitc of the group
group 8, they have full outer shell
what are the 2 paterns between periodic number/ groups and electron configuration
1- the number of outer shell electrons is equal to the number of groups
2-the number of occupied electron shells is equal to the period number
what are isotopes
different atoms of the same element, which have the same number of protons but different number of neutrons
isotopoes vs chemical properties
isotopes have the same chemical properties because they have the same number of electrons and therefore same electronic configuration
how do you calculate the relative atomic mass of an element
sum of [(atomic mass × % abundance)] for each isotope/ 100
how do you calculate total relative abundance
sum of [(atomic mass × % abundance)] for each isotope/ average mass
describe group 1 in periodic table
they are alkali metals, lithium, sodium, potassium and are relativly soft metals
going down the group:
-decreasing melting point
-increasing density
-increasing reactivity
what happens when you react a metal with water
produces the metal hydroxide and hydrogen
what can be observed when a metal reacts with water
you would observe the metal disappearing, and some gas bubbling off surface and if alklai metals that react, would give off heat
what is the name for the test fro hydrogenb
lit splint squeaky pop
describe group 7 + trends
the halogens, chlorine, bromine and iodine, they are diatomic non-metals (eg Cl2)
as you go down the group:
-increases density
-decreases reactivity
-meltingpoint increase
what is the appearane of chlorine in room temp
a pale yellow-green gas
what is appearance of bromine in room temp
red-brown liquid
what is appearance of iodine in room temp
grey-black solid
describe transition elements
metals that have, high densities, melting points and form coloured compounds, they also often act as catalysts as elements and in compounds
they also have elements which have ions with variable oxidation numbers eg. iron (2)-> 2+ and iron (3) -> 3+
describe group 8
they are noble gases which are, unreactive (because of full outer shell), monoatomic gases (because they have full outer shells)
what is a displacement reaction?
A reaction where a less reactive element is removed from a compound by a more reactive element. is a redox reaction.
how do you tell a displacment reaction has occured?
temp change, colour change, a percipitate is formed
what is the reactivity series less to more
gold, silver, copper, hydrogen, iron, zinc, carbon, aluminium, magnesium, calcium, lithium, sodium, potassium