periodic table
what did Dmitri mendeleev do
the periodic classification of the chemical elements
what is the mole in chemistry
a very important unit of measurement that chemists us
what is the electron dot structures
a way to show the number or valence electrons in a atom.
what are electrons
a stable negatively charged component of an atom
how many elements are there on the periodic table
118
How is a mole defined?
A mole is defined as 6.02214076 × 1023
what is the octet rule
atoms gain or lose electrons to attain an outer shell electron configuration nearest that of a noble gas
What do electrons do
create a negative charge that balances the positive charge of the protons in the atomic nucleus.
how many non metals are there on the periodic table
Seventeen elements
How is a mole calculated?
divide the mass of the material by its molar mass.
what does the number of valence electrons tell you
the group the elements are in
What are the 3 types of electrons
ionic, covalent, and metallic
how many metals are on the periodic table
92
What is Avogadro’s number?
6.02214076 × 10'23
an ionic bonds form from what
the attraction between a positive and negative ions
Why are electrons so important?
Electrons give the atoms the volume, shape etc. Without the electrons, the atoms will be positively charged. Without the electrons, the atoms cannot form bonds with each other.
how old is the periodic table
150 years old
freebie
you are very lucky
what is ionic and covalent bonding
Covalent bonding involves the sharing of electrons between two or more atoms. Ionic bonds form when two or more ions come together and are held together by charge differences.
What is electron made of?
Each electron has an electrical charge of -1