1c - atomic structure Flashcards
how to calculate Rf value
distance travelled by solute/distance travelled by solvent
what is an atom?
the smallest particle of a chemical element that can exist. its made up of protons, neutrons and electrons
what is a proton?
a particle in an atom. it is heavy and positively charged
what is a neutron?
a particle in an atom. it is heavy and neutral
what is an electron?
a particle in an atom. it has hardly any mass and is negatively charged
what is a molecule?
a group of atoms joined together.
what is in the nucleus of an atom?
- its in the middle of the atom
- it contains protons and neutrons
- has a positive charge
- almost the whole mass of it is in the nucleus
what are isotopes?
different atomic forms of the same element, which have the same number of protons but different numbers of neutrons
how to calculate relative atomic mass
(isotope mass x isotope abundance) x 100
what is the atomic number?
the amount of protons in the nucleus of that element. it is the number below the element on the periodic table
what is the mass number?
the amount of protons and neutrons in the nucleus of that element. it is the number above the element on the periodic table.
