Periodic Table And Atomic Stucture Flashcards
How is the periodic table arranged
The elements in order of increasing atomic number
What can the periodic table determine
Wether an element is metal or non metal
What are groups in the periodic table
Groups are columns containing elements with the same number of outer electrons indicated by the group number
What do elements in the same group have in common
Elements within a group share the same valency and have similar chemical properties because they
have the same number of electrons in their outer energy levels.
What makes up an atom?
A nucleus, containing protons and neutrons, and electrons orbit the nucleus
What charge does a proton have
positive
what charge does a electron have
One - negative
What charge does a neutron have
Neutral = 0
What mass does proton, neutrons and electrons have
Protons and neutrons have an approximate mass of one atomic mass unit and electrons, in
comparison, have virtually no mass.
What is the atomic number
The number of protons in an atom
How do u know the number of electrons and protons are the same
In a neutral atom the number of
electrons is equal to the number of protons.
What is the mass number
The mass number of an atom is equal to the number of protons added to the number of neutrons
What are isotopes
Isotopes are defined as atoms with the same atomic number but different mass numbers, or as
atoms with the same number of protons but different numbers of neutrons.
What is nuclide notation
Nuclide notation is used to show the atomic number, mass number (and charge) of atoms (ions)
from which the number of protons, electrons and neutrons can be determined.
How is ram calculated
The average atomic mass has been calculated for each element using the mass and proportion of
each isotope present. These values are known as relative atomic masses.
What do covalent bonds for between
Non metal atoms
What is a covalent bond
A covalent bond forms when two positive nuclei are held together by their common attraction for a
shared pair of electrons
How can simple molecules be described
These molecules can be described as linear, angular, trigonal pyramidal or tetrahedral.
How. many bonds can be formed between atoms
More than 1
What are the 7 diatomic molecules
H2, 02, N2, F2, Cl2, Br2, I2
What is an element
An element is a substance made out of one type of atom
What is a compound
A compound is when 2 or more different elements chemically join/bond together
What is a molecule
A molecule is 2 or more atoms
What percentage of the periodic table is metals
80%
What percentage of the periodic table is non metals
20%
What is group 1
Alkali metals
What is group 2
Alkaline Earth metals
Between group 2+3
Transition metals
Group 7
Halogens
Group 8
Noble gases
Why don’t the noble gases react
The noble gases have a full outer energy level . This makes them unreactive and stable
If a molecule has 2 atoms what shape is it?
Liner
If a molecule has 3 atoms what is its shape called?
V-shaped or angular
If a molecule has 4 atoms what is its shape called?
Trianganal pyramidal
If a molecule has 5 atoms what is its shape called?
Tetrahedral
Mass of an electron
1/2000
Mass of proton
1
Mass of neutrons
1
What does covalent molecular substances have between molecules
weak forces
Do covalent molecular have high or low melting or boiling points
Low melting and boiling points
Do covalent molecular substances conduct electricity
No because they do not have charged particles which are free to move
Do covalent networks have strong bonds or weak forces
Strong bonds within one giant structure
Do covalent networks have low or high melting and boiling points
High because the network of strong bonds is not easily broken
Do covalent networks dissolve or conduct
No beca they have no charged particles that are free to move
What are ions
Ions are formed when atoms lose or gain electrons to obtain the stable electron arrangement of a
noble gas.
Generally what charges are metals and non metals
In general, metal atoms lose electrons forming positive ions and non-metal atoms gain electrons
forming negative ions. Ion-electron equations can be written to show the formation of ions through
loss or gain of electrons.
What are ionic bonds
The electrostatic attraction between positive and negative ions. They want to become stable Ionic bonds transfer electrons
What ionic compounds structure
3D lattice
Do ionic compound have high or low melting and boiling points
High because strong ionic bonds must be broken in order to break up the lattice
In general are ionic compounds soluble in water
Yes
Do ionic compounds conduct
Yes but only when molten or in solution as the lattice structure breaks up allowing the ions to be free to move
If a compound has 2 elements it ends in what
‘ide’
If the compound ends in ‘ite’ or ‘ate’ what does this tell us
That oxygen is present
mono
1
di
2
Tri
3
Tetra
4
Penta
5
Hexa
6
Hepta
7
Covalent bonds exists between what
Non metals only
Ionic bonds exists between
Compounds ie metals and non metals
What is electricity
The flow of electrons
