Atomic Stucture And Periodic Table Flashcards
What is Ar?
Relative atomic mass.
What is the relative atomic mass of an element?
The average mass of its isotopes compared with the mass of an atom of carbon-12.
What is a single atomic mass unit?
The mass of a carbon-12 atom divided by 12.
What is the relative formula mass for a compound?
The sum of the relative atomic masses of all the atoms in the chemical formula.
What is Mr?
Relative formula mass OR relative molecular mass.
What is the relative molecular mass of a molecular compound?
The same as the relative formula mass.
What is the definition of an isotope?
Atoms with the same number of protons but different numbers of neutrons.
Is there a difference in chemical properties between isotopes?
No they are chemically identical as they have the same number of electrons which determine how an atom reacts.
How would you work out the average relative atomic mass?
(Percentage X atomic number) etc.
———————————
100
What is the relative mass and charge of a proton?
Mass: 1 Charge: +1
What is the relative mass and charge of a neutron?
Mass: 1 Charge: 0
What is the relative mass and charge of an electron?
Mass: 0 Charge: -1
What is the atomic number?
The number of protons/electrons in the atom. Sometimes called the proton number.
What is the mass number?
The sum of the protons and neutrons in the atom. Electrons have negligible weight.
