Key Area 2: Atomic Structure Flashcards
Group 1?
Alkali metals
Group 2?
Alkaline earth metals
Group 7?
Halogens
Group 8?
Noble gases
Two elements liquid at room temp?
Bromine and Mercury
Protons location and charge?
Nucleus, 1+
Neutrons location and charge?
Nucleus, 0
Electrons location and charge?
In shells orbiting nucleus, 1-
Equal numbers of?
Protons and electrons
Mass number?
Top, protons + neutrons
Atomic number?
Bottom, protons
First shell?
2 electrons
Second shell?
8 electrons
Third shell?
8 electrons
Ions
when there is an imbalance of the no. of positive protons and negative electrons
Mass no. - atomic no. =
neutrons
metal Atoms loose electrons ions form?
positive charge (ion)
non-metal Atoms gain electrons ions form?
negative charge (ion)
Isotopes
have the same atomic no. but their mass number can be different
RAM
Relative Atomic Mass is the average mass of an atom in an element taking into account their relative proportions
Atoms can be represented by?
Nuclide notation
Covalent bond forms between?
Non-metal atoms, forms when two positive nuclei are held together by their common attraction for a shared pair of electrons
The shape of simple covalent molecules depends?
On the number of bonds shared, these molecules described as linear, angular, trigonal pyramidal or tetrahedral.
Covalent molecular substances
have strong covalent bonds within the molecules and only weak attractions between the molecules
have low melting and boiling points as only weak forces of attraction between the molecules are broken when a substance changes state
do not conduct electricity because they do not have charged particles which are free to move
CMS which are insoluble in water may dissolve in other substances
Covalent network structures
have a network of strong covalent bonds within one giant structure
have a very high melting points because the network of strong covalent bonds is not easily broken
do not dissolve
in general, they do not conduct electricity, because they do not have charged particles which are free to move
Ionic compounds
form lattice structures
have high melting and boiling points because strong ionic bonds must be broken in order to break up the lattice
soluble in water
Elements within a group share similar chemical properties because they have?
The same number of electrons in their outer energy levels
