atoms ions and compounds

what is an isotope

atoms of the same element with different numbers of neutrons and different atomic masses

What is the A number?

the mass number

What is the Z number?

The proton number

what is the same between isotopes of the same element

different isotopes of the same element have the same number of electrons, and neutrons do not effect the way an element reacts. so all isotopes will react the same way

what is the relative mass of an electron

1/1836

what is the relative atomic mass of an element

the weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon-12

what is relative molecular mass and how do you calculate it?

compares the mass of a molecule with the mass of an atom of carbon 12. to calculate it ass up the all the relative atomic masses of the elements making up the molecule

what is relative formula mass?

compares the mass of a formula with the mass of an atom of carbon -12

what is mass deflect?

the stronger the nuclear force holding together protons and neutrons the more mass lost as a result

what is a standard isotope

a standard isotope is used to base all atomic masses. carbon 12 is used

how do you measure the mass of an isotope

an atomic mass of unit (u) is used. carbon 12 is defined as 12 u. the standard mass for atomic mass is 1 u

what is relative isotopic mass?

relative isotopic mass is the mass of an atom of an isotope relative to 1/12th go the mass of an atom of carbon -12

equation for working out relative atomic mass

Ar = (the sum of (abundance x Ar)) /100

what is an ionic equation

describes the essential character of a reaction involving the reacting ions only. spectator ions are left out

what are the rules for writing out an ionic equation?

1. write out the balanced equation
2. for aqueous ionic substances write out the ions separately
3. leave all the formula for solids, liquids and gases the same.
4. cancel all the spectator ions that appear on both sides of the equations

hydrogen ion

H+

lithium ion

Li+

sodium ion

Na+

potassium ion

K+

Rubidium ion

Rb+

caesium iom

Cs+

ammonium ion

NH4+

Magnesium ion

Mg2+

calcium ion

Ca2+

strontium ion

Sr2+

Barium ion

Ba2+

silver ion

Au+

zinc ion

Zn2+

aluminium ion

Al3+

nitrogen ion

N3-

Phosphorus ion

P3-

oxide ion

O 2-

Sulfur Ion

S2-

fluoride ion

F-

Chloride Ion

Cl-

bromide ion

Br-

iodide ion

I-

carbonate ion

CO3 2-

sulfate ion

SO4 2-

sulfite ion

SO3 2-

Dichromate ion

Cr2O7 2-

phosphate ion

PO4 3-

hydroxide ion

OH-

Nitrate ion

NO3-

nitrite ion

NO2-

Hydrogen carbonate ion

HCO3-

what is the equation or phosphoric acid