2 - Atoms, Ions and Compounds Flashcards
What is Sulphate and it’s Charge?
. (-2)
S O
4
What is Nitrate and it’s Charge?
. (1-)
N O
3
What is Hydroxide and it’s Charge?
. (1-)
OH
Give the formulae for Aluminium Sulphate?
Al wants to get +3
SO4 has a charge of -2
So Al x 2 and SO4 x 3
Al2(SO4)3
What is Carbonate and it’s Charge?
. (2-)
CO
3
What is Ammonium and it’s Charge?
. (1+)
NH
4
What is Zinc ion and it’s Charge?
. (2+)
Zn
What is Silver ion and it’s Charge?
. (1+)
Ag
What is the formula of potassium sulphate?
Sulphate ion (SO4) has a charge of -2.
Potassium forms a charge of +1
So for every one sulfate ion you need two potassium ions to cancel out the charges.
Formula = K2SO4
Charges on an ionic compound must always balance out to what?
Zero.
What are ions?
A positively or negatively charged atom or a group of atoms, where the number of electrons is different from the number of protons.
How are ions formed?
When electrons are transferred from one atom to another.
What are cations?
Positive ions, fewer electrons than protons.
What are anions?
Negative Ions, atoms with more electrons than protons.
What does (aq) state symbol mean?
Dissolved in water
What is the definition for the Relative Atomic Mass?
The weighted mean mass of an atom of an element, compared to 1/12 th of the mass of an atom of carbon-12.
What is a binary compound?
A compound that contains only two element.
What is the definition for Relative Isotopic Mass?
The mass of an atom of an isotope, compared with 1/12 th of the mass of an atom of carbon-12.
What is the difference in type of number for the relative atomic mass and relative isotopic mass?
RAM is an average so is not usually a whole number.
RIM is usually a whole number. (One mass)
What is an isotope?
Isotope of an element are atoms with the same number of protons but different number of neutrons.
When is the relative molecular mass used and when the relative formula mass is used?
Relative Molecular Mass - simple molecules
Relative Formula Mass - compounds with giant structures (ionic and giant covalent)
What is a mass spectra used for?
To work out the relative atomic masses of different elements.
On a Mass Spectrum what is on the y-axis and x-axis?
Y-axis: % abundance of ions
X-axis: Mass/Charge (relative isotopic mass)
