The Periodic Table Flashcards
periodic table
an arrangement of elements in order of increasing atomic number
what are vertical columns called?
groups; 1-8 ; transition metals not included ; elements in the same group have similar chemical properties
Group 1
Alkali metals
group 2
alkaline earth metals
group 7
halogens
group 8
noble gases
what does the number of the group indicate
how many electrons the atom has in its outer shell
what are the atom electron diagrams called
bohr structures
what is the smaller number
atomic number
what is the bigger number
mass number
what is the atomic number equal to
protons and electrons (bc atoms are neutral)
how to find neutrons
mass no - atomic no
what to include in a bohr diagram
nuclear formula, electron configuration, label orbits n=1
remember when drawing electron orbits
2 on first, 8 on rest
what are ions
charged atoms
when does an atom become a positive ion
when it loses electrons in chemical reactions
when does an atom become a negative ion
when it gains electrons in chemical reactions
electron configuration of when sodium reacts with chlorine
na —- na+
2,8,1 —–2,8
ionic bond
the force of attraction between positive and negative ions binding them together in chemical reactions, forming molecules
how are ratios calculated?
since each Ca loses 2 electrons, and each chlorine atom gains 1 electron, ratio is 2:1
define molecule
a group of atoms joined together. The smallest particle of an element or compound that can exist on its own
define covalent bond
a type of chemical bond that involves sharing electrons eg H2O
define lone pair
A pair of electrons not involved in bonding in a covalent bond
chemical bond
the force of attraction that holds a molecule together
explain an example of a covalent bond
H2O : hydrogen has 1 elecron, oxygen has 6.
Oxygen attracts 2 hydrogen atoms who share their electrons with oxygen. there is one lone oxygen pair who is not paired with any hydrogen electrons but thats ok. they’re not sad
