Chapter 2 - Atoms, ions and compounds Flashcards
What is the mass of an electron?
1/1836th the mass of a proton
What is atomic number?
The number of protons in the nucleus of an atom
What is an isotope?
An atom of the same element with different numbers of neutrons
Why do isotopes have the same chemical properties?
They have the same number of electrons
What is an ion?
A charged atom
What is a cation?
A positively charged ion, with fewer electrons than protons
What is an anion?
A negatively charged ion, with more electrons than protons
What is relative isotopic mass?
The mass of an isotope relative to 1/12th the mass of an atom of carbon-12
What is relative atomic mass?
The weighted mean mass of an atom of an element, relative to 1/12th of the mass of a carbon-12 atom
How are the percentage abundances of isotopes in a sample of an element found?
Using a mass spectrometer
How does a mass spectrometer work?
The sample is vaporised and then ionised to form positive ions. These are then accelerated, and detected on a mass spectrum as a mass to charge ratio
What is a binary compound?
A compound composed of two elements
What is a polyatomic ion?
A charged group of covalently bonded atoms
What is the formula for an ammonium ion?
NH4+
What is the formula for a hydroxide ion?
OH-
